Where do Macedonians and Slovenians come from?

Idk why but I find Yugoslavia to be an interesting topic. That being said, where do Macedonians of Yugoslavia and Slovenians come from? If you look at the other Former Yugoslavian countries (Bosnia,Serbia,Croatia,Montenegro) you see that their FIRST states were formed MANY years ago, even before the year 1000 AD. But with Slovenia and Macedonia, it shows (for example on wikipedia, and i know wiki isn't the best source) that Slovenia and Macedonia got their independence in 1991, which is just 20 years ago. Before the whole Yugoslavia era, and even before the ottoman empire, where did Slovenians and Macedonians come from? It seems that Bosnians, Croatians, Albanians, Montenegrins and Serbians have been in that area of south eastern europe of hundreds of years, so where did Slovenians and Macedonians come from?