Slovenians came to this place, originally inhabited by Illyrian and Venetic tribes, in the 6th or 7th century, during the famous South Slavic migration. They gradually pushed aboriginal peoples out from Illyria and settled here, sometimes together with Germanic and many Asian nomadic nations, destroying Roman towns and settlements. Actually, there was practically no original language substratum in this region at that time: so many different peoples passed through North Adriatic coast during the Great Move of nations, in the 4th - 6th centuries.
Slovene suffered great influence from German, as Slovenia was early conquered by Austrian dukes. That influenced the dictionary, but practically did not cause any changes to the grammar, so it remained purely Slavic. Slovene is referred to South Slavic subgroup, though it represents the stage somewhere between Western and Southern subgroups. Its grammar doesn't look like Bulgarian or Macedonian a lot, Slovene has no articles and it is highly inflected; the morphology sooner reminds Czech, together with the dictionary. The phonetic development is very similar to both Western and Eastern Slavic languages - sibilants were derived from Proto-Indo-European labiovelars and palatal stops. There are 6 cases of nouns, vocative and ablative disappeared. Locative and instrumental cases can be used only with prepositions. Three numbers are still in use, and dual is used quite widely, in nouns, pronouns and verbs. Three grades of demonstrative pronouns were preserved (this I have, this you have, that).
Verbs have present, past, future tenses, imperative and subjunctive moods. Past (derived from Common Slavic perfect), future and subjunctive are formed analytically from the Slavic participle in -l, with use of auxiliary verb "to be" in this or that form. Among verbal forms infinitive and supine can be named. The prepositions can stand before nouns in genitive, dative, accusative, locative and instrumental.