Celtic tribe Segestani. It was a Celtic-Illyrian tribe basically, they started one of the oldest towns in that region, Siscia or today Sisak. That town was also the capital city of Pannonian Croatian Principally.

Every year there is a festival "Celtic Nights" preformed there
image  :D

I have some family in that town.

It is probably the most fertile land in this part of Central Europe, thus so many wars over it in history…thought originally inhabitants were Illyrians, later Celto-Illyrians after they merged.

Interesting that Croats celebrate all elements of their roots, be it Slavic, Germanic or Celtic, as I have seen on this forum (also Sarmatism was practiced in history). Shows good awareness of one's roots and that blod is thicker than water.

Here in Poland, there are also some Germanic traditions practiced (Sarmatism was also once practiced), but to my knowledge, no Celtic ones (though only Silesia was once Celtic land). Perhaps I make thread about other European traditions practiced by Slavs, would be interesting thread.

Pannonians: http://en.wikipedia.org/wiki/Pannonians#Pannonian_tribes
Pannonia is Slavic Homeland by early Slavic chronicles and some modern Slavists.

Ah, I thought so about Pannonian tribes being one of Illyrian ones.
By SLavic homeland, you mean one that some Slavs claim to be root of Slavic peoples (Danubian theory), or just one of them?