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A Comparative Latin Grammar

1. History of the Latin Language
Archaic Latin Period
Popular Latin Period
2. Comparative Phonetics
3. Noun System
4. Adjectives
5. Pronouns
6. Numerals
7. Adverbs
8. The Verb
9. Verbal Nouns
10. Auxiliary Parts of Speech

       § 1. History of the Latin Language.

The Latin language was doomed to became a universal one, once being just a small dialect of a district in ancient Italy. It was the language of the powerful Roman Empire, but even when it collapsed and was occupied by barbarians, the language did not disappear - moreover, it was flourishing for ages after the fall of Rome. About two thirds of all medieval European literature was written in Latin, and the higher society used it in everyday life. Latin was the official language of the Catholic church, the only source of education at that time in Western Europe. After the Pope lost all his authority, and Latin was replaced by national languages in literature and colloquial speech, all European tongues appeared having a large percentage of Latin words in themselves. The whole spheres of the English, French, German or Russian languages are composed of Latin words only. We think we do not know Latin unless we studied it: but since we are born we pronounce Latin words every day - 'lamp', 'video', 'calendar', 'card', etc. Latin is still a living language - it is dissolved in our everyday speech, it is written in every book, it is known by everyone.

Officially, Latin is spoken only in Vatican now. This situation is quite similar to that existing long ago, when in the 8th century BC Rome was founded at that very spot. In ancient times Latin became the most powerful tongue in Europe and penetrated into the speech of people all over the world.

See essay: The Origin of Rome and Romans

Italic migrants arrived in Europe, as we can suppose, together with a few other Indo-European nations. In the 14th century BC the great migration wave departed from the Pontic region to the Northern Balkans (see Indo-European Chronology). It is well witnessed by the materials of archaeology, and partly by historical data too: this very wave was the catalyst which caused the Doric invasion to Greece. Doric tribes came to the Balkans either simultaneously with Italics, or a bit before them. The punch of nations which arrived in Europe also included Illyrians, Celts and Venetics. They all spent some time on the Balkan peninsula, contacting actively with the previous newcomers - Phrygian and Thracian. Then the horde divided: Illyrians stayed on the Balkans (in modern Hungary, Yugoslav countries, and Albania), and Italic, Venetic and Celtic moved further to the west.

In the 12th century BC, the first wave of Italic population arrived to the Apennine peninsula. This date is often challenged: another theory is that Italic people came to their new homeland by two different ways - the first one in the beginning of the 2nd millennium BC from Illyria across the Adriatic (these were Latin, Siculian, Faliscan) and the second a thousand years later from the north - these were Oscan and Umbrian. Some linguists suggest that those two branches are not Italic, but belong to different groups. The peculiarities of ethnic distribution in ancient Italy proves that migrants did not always come from the north, from Europe. Another brilliant example is the Etruscan appearance in Italy - they occupied lands on the west shores of the peninsula, arriving definitely from the Tyrrhenian sea.

Anyway, the Latino-Faliscan subgroup of Italic is often considered as an ancient one. Different from Osco-Umbrian, it does not have so much in common with Doric Greek, Celtic and Illyrian, and is rather original. It consists of three principal languages, as far as we know today: Latin itself, spoken in Latium on the west coast of Central Italy; Faliscan, a mixture of Italic and Etruscan speech in a small region in Etruria; and Siculian, a language insufficiently explored, spoken on Sicily and influenced greatly by non-Indo-European tongues of the island.

Of all three, Latin is the only which is studied well, but the comparative analysis within the subgroup is often impossible. Still, one of the most valuable sources is the Old Latin, or Archaic Latin language, preserved in several inscriptions from the 8-5th centuries BC. Latin was a rather progressive tongue and changes occurred very fast throughout the historical period of its development, so Old Latin words and morphology units are of great importance to the studies of the language.

Archaic Latin

Sources for studying the Archaic stage of Latin are rather scarce. Linguists define the time frame of the period from the 8th to the 5th century BC. Romans and citizens of other towns in Latium acquired the script in the 8th century from Italian Greeks whose colonies existed in Cumae and Neapolis, close to Rome. We will not describe the Roman script and its development in detail, but you can turn to a special page devoted to it (Roman Alphabet) instead. It seems that Etruscans who were at the time much more civilized than Italics gave them first skills in writing. But Latin people in fact did not use much of it, they were occupied by primitive agriculture and wrote no literature works. That is why inscriptions written on columns and walls of temples are the only thing left from Old Latin.

The earliest of them, as far as modern science has discovered, is the inscription on a fibula (a sort of a golden adornment) from Praeneste. It dates back from the late 7th century BC and reads the following:

Manios med fhe fhaked Numasioi
(Classical Latin Manius me fecit Numerio)
Manius made me for Numerius

Another quite ancient inscription is that found on the so called "black stone" which was found during archaeological works on the spot of the Roman forum. It is dated around 500 BC and reads:

quoi honc… sakros esed
(Classical qui hunc… sacer erit)

Other Archaic Latin inscriptions were written later and contain usually just a few words, mostly personal names, which is typical for ancient written examples. They were mostly written on burial stones, and only a few are official documents of the rising Roman Republic. Among them the most famous are the epitaphs of the Scipio family and the text of the Senate's order concerning temples of Bacchus in Rome.

The above mentioned documents allow us to get acquainted with the ancient stage of the Latin language, to understand better processes which were under way later. Archaic Latin stands much closer to the Proto-Indo-European stage. In phonetics, its major characteristic feature is the preservation of diphthongs, which were later partly simplified, partly disappeared. The examples are:

  ai was preserved in cailavit, aire (in Latin turned to ae: caelavit, aer). Latin words borrowed from Greek with this diphthong also made it ae (Thermopilae)
  au became long o in Classical Latin, though it was present in Archaic Latin: maurtia is the example (Latin mortis 'death')
  ei also became a monophothong, long e in deus (Archaic Latin deivos); another variant was long i in sive, si (Archaic Latin seive, sei 'if')
  oi changed its pronunciation to oe (Latin foederatio, Archaic Latin foideratei); this very oi turned to long u sound when in the beginning of the word: oino 'one' becomes unus, una in Latin, and the word comoinem (Classical Latin communem is the derivative from the same word unus with a prefix com- 'together', 'with')
  Archaic Latin shows a strange diphthong which did not exist in Proto-Indo-European and was probably an Italic innovation: oe in coeravit 'he cured', Classical Latin form curavit with long u
  again two different ways of reflection of the diphthong ou which existed in Archaic Latin met in the words iouestod, souad (Classical Latin developed u here) and cloulei (later oe)

The preservation of diphthongs is thus an archaic feature which later disappeared in the language. Oscan as the most conservative among Italic languages, preserved all them too, while Umbrian did not have the majority of them.

Archaic Latin phonetics used a number of other vowels which were changed in certain positions in the Classical period. But most of them were changed just due to assimilation processes:
a changed to e (Archaic Latin muliar, cuncaptum)
e to i (Archaic mereto, Classical merito 'by merits')
o to i (Archaic Primogenia, Classical Primigenia)

The letter u in Archaic Latin sometimes sounded a bit like modern German ue, and that is why could be replaced by i; later this sound coincided with original i. The example of this is Archaic lubs, Classical libens, liber (from IE *leudh- 'free people').

Old Latin consonants did not undergo those important changes we seen in the Classical period. Many original Italic phonemes sounded still archaic. For example, the initial b- in Latin bonus 'good, kind' originated from Archaic Latin dv- (dvenoi). Consonant sounds did not yet disappear in weak positions: like -v- between vowels in deivos 'a god', Latin deus. The final -d (which is quite important for the noun declension, because it was in the ablative singular ending) was still on its place; later it was dropped.

And one of the most significant features - Archaic Latin did not know the law of rhotacism, it preserved -s- between vowels (Numasioi > Nomerio, vetusia - Classical vetoria). This proves that rhotacism is not a Common Italic trait, it appeared rather late, but simultaneously in Latin and Umbrian (but not Oscan).

Other consonant changes are mostly kinds of assimilation (suepnos > somnus, adcedo > accedo, conquatsai > concussi)

Latin morphological system is the result of graduate simplification of the Indo-European original structure. The number of cases decreased, as well as the number of verbal grammar forms - moods, tenses, etc. Latin produced more analytic forms, which is typical for all Indo-European branches.

Classical Latin

The Latin language in its classical form shall be the main subject of the present research. It was developing together with the growth of Rome and its empire. Already the works written by Plautius (2nd century BC) though chronologically is referred to the Archaic period, actually demonstrate a language closer to Classical Latin. Latin becomes more expressive, it is now used not only for documents in the Senate and burial inscriptions - but mainly for literature works and poetry, which flourished in Rome at that time. Classical Latin time lasted from the 2nd century BC to the 2nd century AD, and writers and poets which wrote in it include Cicero, Caesar, Horatius, Ovidius, Vergilius. Phonetics was finally fixed, morphology acquired complex analytic forms of verbal declension (like plusquamperfect and a branched system of subordinate clauses). Syntactically the language became quite strict - there were exact laws of writing and giving speeches.

Simultaneously Latin was brought to the lands conquered by Romans. Italic tribes were the first who lost their original tongues and picked up Latin; then Gauls, Etruscans, and many other tribes of ancient Europe took it up. Etruscan, for example, once being a powerful language of all Italy, was forgotten rather quickly: in the 1st century AD Varro composed an Etruscan dictionary, and he complained that it was hard to do that - nobody spoke Etruscan at that time.

Latin in its Classical variety was thus accepted by numerous nations in provinces, becoming an international language. But what a paradox: that meant also the end of Classical Latin.

Popular Latin

Ordinary people in Rome and its colonies all over Europe and Near East actually never spoke the Classical language which was used for the upper society of citizens, in written works or in public speeches. The popular speech was much simpler, less complex in syntax and already in the beginning of the new era differed rather considerably from Classical Latin. Its is always hard for us now to define how the language of ordinary people sounded - for example, the same thing goes for Greek or Hittite, or Vedic: it is natural to suppose that illiterate peasants and simple citizens spoke in a different way from the language of manuscripts, Homer's works or Hittite king's edicts. The impossibility to study the popular language leads us sometimes to wrong conclusions regarding the reconstructed Proto-Indo-European language. In our reconstructions and analysis we can base upon classical literature works, but rarely on popular colloquial speech. According to Antoine Meillet, elements of vernacular Proto-Indo-European are found, for example, in doubling consonants in the root (like Greek gunnis, Latin lippus), which denoted expressive lexicon, or in words with original Indo-European *a in the root (atta, akka, Sanskrit ajá); this *a appeared rather rarely in Indo-European roots.

Popular Latin gives us more opportunity than any other ancient language to judge about the Latin language as a whole. We are sure that Popular Latin existed much earlier than the 3rd century AD, when it was first witnessed in documents. Cicero and Quintillianus, legislators of Classical Latin, never spoke it in the family or in personal letters. Cicero himself wrote once to a friend: "How do I look in letters? Don't I really speak like a plebeian? We write court documents in a more decorated language, but write letters in everyday words". Quintillianus, author of "Education of orator", wrote: "I think that the vulgar speech possesses one set of features, while the speech of an educated person - another". The first thing that attracts our attention in these words is that both authors find it quite natural that the language should be different for different purposes.

The studies of Popular Latin is difficult first of all because nobody actually wrote in it on purpose. Its elements penetrated into the text depending on the level of education of the author (to be more precise - on the level of lack of education). That is why it is quite complicated to reconstruct the whole language. That is why research is often made on the basis of Romance languages, the direct descendants of Popular Latin. A brief example: Spanish canudo, Italian canuto, French chenu 'grey-haired' should be heirs of some Popular Latin form canutus, not Classical canus. But this word remained reconstructed and was long marked by (*), until this word was successfully found in one of Plautius's poems.

Latin was brought to Italy in the 2nd century BC by Roman colonists, and since then the language began to transform: it made aboriginal tongues disappear, but at the same time acquired a great number of features from them. Popular Latin borrowed much from Umbrian, and therefore began more progressive. The number of changes to the language increased when Romans reached Gaul and Spain. Numerous Celtic borrowed words, words from other European languages transformed Latin gradually into Romance. Moreover, different dialects of Popular Latin emerged in provinces according to the linguistic distribution of substratum speech. That is how Iberian Romance, Gaulish Romance and Dacian Romance appeared in the firs centuries of the AD era.

We would like to depict here some characteristic traits of the Popular Latin language.

In phonetics:
1. Vowels lost its division into long and short: most of them began short in all dialects of Popular Latin;
2. Prosthesis appeared: an i was added if the word began in sp, sc, st (like Latin statio > Spanish estacio)
3. Many diphthongs disappeared, mainly in Gaul, Italy and Spain (aurum > orum)
4. t, c, d,g changed their pronunciation before vowels e and i (gratia sounded in Latin like [gratia] while in Popular language it became [gratsia])
5. The combination -ct- had different reflections in the East and the West: like it in Gaul and Spain, but pt in Dacia (Latin factus > French fait)
6. A great lot of vocals and consonants disappeared at the end of the word, sometimes the whole final syllable disappeared (quomodo > com)

In morphology:
1. The article is appearing in Popular Latin. This is supposed to be a universal feature of practically all Indo-European groups when they reach "the article stage" of development. Of modern IE branches, only Baltic and partly Slavic never knew the article. Usually the definite article appeared first, and was generated in most cases from the demonstrative pronoun. This was also the case with Latin, which made an article of the demonstrative pronouns ille, iste (Gaulish, Iberian, Italian, Dacian used ille, Sardinian and Catalan chose iste > su, sa, sos). The article was placed before a noun in the West, but followed it in Dacia - due to the influence of the Balkan language union.
2. The system of noun declension was simplified greatly: the types of declension (5 in Latin) coincided, and the number of cases greatly decreased.
3. The neuter gender disappeared.
4. In verbs, practically all synthetic verbal forms (like tenses, moods, types of conjugation) were replaced by analytic, or complex, forms. The perfect was no longer expressed by special endings and a special stem, but by a combination of the verb habere + the past participle form. Most Romance languages still use this very form.

Popular Latin was actually not a language as we are used to understanding this term, but some process of transition of the Latin language into separate Romance languages. It is very important for the studies of Romance languages as a whole - actually Romance is the only Indo-European group of languages which we can trace back to its "proto-language". Its proto-language is Latin.

       § 2. Comparative Phonetics.

When we started this project, the most complicated task for us was to make this one really unique on the Web, original in its contents. There are at least three or four good Latin grammars online, and we will not dare to compete with them. But what we wanted to reflect in this description of Latin, is its comparativeness. Grammars often demonstrate a language as it is, giving facts, giving charts and words but without any historical and comparative analysis of what the language is like from the point of view of Indo-European linguistics. We would like to show the Latin grammar in context of the whole Indo-European studies. That means that phonetics should not be just a description of sounds and sound combinations, but also a look inside, into deeper and more ancient times when the Latin language was just about to appear.

Latin vowels consisted of both long and short, like in any other Indo-European group. That means there were ten of them:

*a, *@
ago < *ag'ó 'I lead', pater < *[email protected]ér 'father'
pedis < *ped- 'foot'
qui < *kwis 'who'
oculus < *okw- 'eye'
super < *s-uper 'above'
frater < *bhrátér- 'brother'
verus < *wér- 'right, loyal'
bibere < *pí- 'to drink'
donum < *dó- 'gift - to give'
mus < *mús- 'mouse'
We need to notice that the Latin orphography does not make a distinction between long and short vowels, so we can find out only from verse or from etymology which vowel was long or short. However, this is not hard to do: for example, the -o in the 1st person singular of Latin verbs is always long (ago, do, facio).

We see that Latin preseved the original vocalic system of Proto-Indo-European quite well, and almost all vowels remained the same. The so called "Indo-European schwa" turned to short a, as everywhere in European languages (in Sanskrit it became i: pitar 'father'). The uniformity of Latin reflection of the schwa is called another proof to the fact that there was only one schwa in PIE (not three, as some suppose), or at least those three merged before Italic separated from the Proto-community.

Although Latin vowels sounded much like their Indo-European ancestors, they show a great variety of different mutations in certain position in the word. Here are some of them listed:

1. According to the law of rhotacism, i and u before a mutating s became e and o respectively (i.e. cenises > cineris, fused > foret) (see below about the law of rhotacism)
2. The reverse rule: e, o turn to i, u before nc, ng, mb, l (e.g. honce > hunc, *embris > imber, *londhuos > lumbus, molta > multa)
3. e can become o before v, l (*neuos > novus, *nelus > nolus)
4. Syncope happens in the middle or at the end of the word, that means that a short unstressed vowel is dropped (*opificina > officina, *perrego > pergo, *dexiteros > dexter, uta > ut)
5. Metathese is a stable feature of sonant syllables - i.e. the vowel changes its place and often pronunciation in the syllable (crino > cerno, *sakrodhots > sacerdos, *tignelom > tigillum)
    Metathese frequently appears also in Germanic languages, for example in Old English, where the same thing often happens in syllables containing r. This is connected etymologically with the specific status of Indo-European syllable sonants which were not actually consonants, like modern English l, m, n, r, but acted alos like vowels.
6. The opposite process to syncope is anaptixe: a short vowel appears in the word to separate two consonants. In Latin this often happened between b and l (*-blo- > -bulo-, -bli- > -bili-).
7. Assimilation of vowel happens when two syllables of the word contain different vowels (*dvenos > *bonos > bonus, where e - o becomes o - o). Assimilation is disabled before r (*veros > verus 'true')

Latin diphthongs were not conserved as stable as the vowels. Some of them were changed in the Classical period, though Archaic texts still remembered them:

*ai > ae (praidad > *praeda 'booty')
*ei > í (*sneigwh- > nix, nivis 'snow')
*ou, *eu > ú
*oi > ú, oe

As a whole, the vocalic system of Latin was rather conservative, comparing to such languages as Germanic, Slavic or especially Indic. However, the accents changed their places: the Proto-Indo-European language based on just two-vowel system: e - o, which constructed practically all syllables (i and u having been special sonant vowels). *a was rarely used in the Proto-language. Latin, as well as many other European tongues, demonstrates a wider use of this sound and in addition a great variety of positional mutations described above. This is what makes the Latin phonetics peculiar.

Now let us speak about consonant phonemes in Latin. According to the classical theory, Proto-Indo-European was especially rich in stop consonant sounds; there were three sets of stops (simple - b, p, t, d, k, g, gw, aspirated - bh, dh, gh, gwh, and palatal - k', g', g'h). The glottal theory, introduced about 15 years ago, challenges this, but as well gives its sets of stops. In any case, stops were much more numerous than fricatives.

This fundamental feature was completely lost in Latin - and the majority of other IE groups too. Here is the table of Latin consonants:

  labial dental palatal velar
stops p, b t, d   k, g, q
affricates   ts    
fricatives v, f s, z j h
sonants m n, r, l    
    a) the letter q represented originally a labiovelar [kw] sound, but in the Classical period it became just another symbol for [k].
    b) the sound [ts] was just appearing in the language, and it became stable only in the 2nd century AD, pronounced in such combination as ti, ci, ce, cae

As we can see, Latin just made three important things with the consonants:
a) threw away the aspirated and palatal stops
b) eliminated semi-vowels *w and *y
c) made sonants simple consonants, while in Indo-European they were a special group of sounds, somewhere between vowels and consonants.

All three made Latin a language of simple consonants, which are easy to pronounce. This is one of the reasons why Latin has become so popular: it is natural that only simple languages can become international, acceptable by other nations. For example, if even you try to make an Indian learn Irish Gaelic sounds, it will take a year to achieve more or less visible results. But anybody can pronounce Latin.

As for the complex Indo-European sounds, they coincided with the simple ones the following way:

*bh, *dh, *gwh > f in initial positions, or v, b, d in the middle of the word
  (*bhratér > frater 'brother',
  *dhwer- > forum 'door - forum',
  *leudh- > liber 'free',
  *medhyo- > medius 'middle')
*gh, *g'h > h, g
  (*gheim- > hibernus 'winter',
  *weg'h- > vehere 'to ride, to drive')
*k', *g' > k, g respectively
  (*weik'- > vicus 'settlement, village',
  *eg'hom > ego 'I')
*kw, *gw > k, qu and g, gu, v respectively
  (*kwis > qui 'who',
  *ngwi- > unguis 'nail')
The combination dw is turned to b (*dvenos > bonus)

Latin is one of languages which try to make the pronunciation system easier through a number of assimilations. This process of assimilation which went on and on during the whole Classical period makes a lot of Latin words and grammatical forms very hard to analyze from the point of view of etymology. For example, it takes much effort to understand that Latin hibernus 'winter' used to be Indo-European reconstructed *gheim-rin-os, related to Slavic zima. Assimilation was popular in later Romance languages too: French used it widely, shortening words and replacing original sounds.

Here are some examples of how Latin consonants could be subject to assimilation:

1. combinations *ds, ts, tt, dt, dht > ss (e.g. *conquatsai > concussí)
2. at the beginning of the word *ps > s (*psabhlom > sabulum 'psalme')
3. everywhere *ms > ns
4. at the end  *rs, *rd > r; ls > l (*tarsejó > torr)
5. *d is always assimilated before c, g, p, f, t, r, l, especially in verb prefixes (*adcédo > accédo 'I move closer')
6. *t, d are lost before b, p (*quidpe > quippe)
7. stop consonants are always assimilated before nasals, and this is very common in Latin (*suepnos > somnus 'a sleep', *petna > penna, *decnos > dignus)
8. Other assimilations, very are not so frequently met in the language, include:
*tl > cl, or at the beginning l (*pótlom > póculum, *tlatos > latus 'brought')
*dl, ld, rl, nl, ln > ll (*sedla > sella)
*mr > br (*gheimrinos > híbernus 'winter')
*dj, gj > i, j (*pedjos > peior 'worse', *Djowes > Iovis 'Jupiter')
*sr- > fr-, -br- (*srígos > frígus 'cold')

The last one is especially interesting for analyzing phonetics: the transition of *sr- into *fr- must have had an interim stage which evidently sounded like *×r-, with the initial sound similar to modern English th in thin. Such sounds (dental affricates) existed in Greek, in Germanic, but in Latin they could not be preserved. Why are some sounds typical for one language but unacceptable for another? Some linguists explain it with the help of psychological reasons, some consider the geographical position of a nation which influences the speech. In any case, there are some laws of phonetic distribution: for example, none of the northern language ever had aspirated sounds, while such sounds are habitual in the south (India, South-East Asia, etc.)

One of the most significant changes of Latin was the law of rhotacism, already mentioned above. The thesis is quite easy: s is changing into r everywhere between vowels. For example, the word mus 'mouse' in genitive becomes muris, originally musis, with the mutation of s between two vowels. The word "rhotacism" comes from rhota, the name for r in Greek. This feature was discovered in Latin long ago, but it was not the only language which used rhotacism in its phonetics. Besides Latin, rhotacism was widespread in Umbrian and Volscian, two languages from the Osco-Umbrian branch of the Italic group. Moreover, this feature existed also beyond the Italic languages: it was quite stable in Germanic (notably West and North Germanic, but not in Gothic). The Old High German word bessere 'better' has a cognate in Gothic batiza, with the preserved z < *s. Modern English keeps the heritage of rhotacism, for example, in the opposition was - were, coming from Old English waes - waeron.

Comparative analysis shows that rhotacism usually went further and could act also at the end of the word. This was the case with both Germanic and Umbrian: at the end of the word the original s turned into r as well: Umbrian pir 'who' (but Oscan pis), Scandinavian gastiR 'guest' (but Gothic gasts). The question of final rhotacism in Latin is rather peculiar: Latin was not so progressive and did not change its s in final position (quis 'who', hostis 'guest'), but we face a weird case with the comparative degree of adjectives which was ending in -ior in masculine, descending from Indo-European *-yos. Either this was the only exception, or this suffix -ior used to have a prothetic vowel at the end - it is subject to discussion.

Another variety of rhotacism is a weird mutation d > r which was well known in Latin. It is believed to have been borrowed from Umbrian or even from some non-Indo-European language, like Etruscan. Examples: Greek Odysseos > Latin Ulyssus, Greek dacrima 'a tear' vs. Latin lacrima, Latin olere 'to smell' vs. odor 'odour'.

Some consonants tend to disappear in Latin: j, v, h are quite unstable between vowels (*trejes > trés 'three', *lavátrína > látrína, *Mávors > Márs, *coviria > cúria). The most significant trait here was the dropped d at the end of the word which changed the ablative singular ending of nouns (praidad > praeda 'booty').

Well, I am afraid this is all a comparative linguist should know about Latin phonetics. Certainly, I can also mention tens of minor features, transitions and mutations which took place in the language, but they are hardly important for any linguistic analysis. Sometimes each exact case requires itw own phonological explanation. One more example: Latin barba, as we may claim, come from the Proto-Indo-European *bhardhá 'beard'. However, according to phonetic regularities described above, *bh here should become f (initial position), so *farba would be natural. But this is the case of the syllabic assimilation, according to which the combination of a syllable with f and a syllable with b gives two b: so *farba > barba. This is a more complicated level of Latin studies.

As a whole, Latin phonological system was more proressive than Oscan, and more conservative than Umbrian. It did not acquire too much phonetics either from Etruscans, as the Faliscan language did, or from the aboriginal population of Italy, as obviously did Umbrian and Picene. Latin was an average language spoken aroung a little region near the river Tiber: but it was doomed to dominate all around Europe.

Now you can check whether you have understood things well from the material above. Here are some Latin words with their original roots; please define which processes took place in them and made them change:

accuso 'I accuse' < *ad-caus-
What is the feature here?

rubus 'reddish' < *reudh-
liber 'free' < *leudh-
What makes those two have different root vowels?

beber 'beaver' < *bhebhrú-
Why not *feber?

unus 'one' < *oinos
What happened to the diphthong?

mater 'mother'
pater 'father'
Is the origin of *a the same?

mos 'a custom' (root mos-)
Make a genitive form with the ending -is

vivo 'I live' < *gwei-
unguis 'a nail' < *ngwi-
Why two reflections of the same *gw?

bis 'twice' < *dwis
Is the consonant change regular?

Now guess which is which:
facultas < *faklitáts rhotacism
avcaps < *avicaps metathese
audibilis < *audiblis syncope
foret < *fused anaptixa

See answers here, and if you could explain all those examples to yourself more or less distinctly, go on to morphology.