Where did you read that? The origin of the Etruscans is a mystery, actually, because of their language, which resembles nothing spoken in Europe or the Middle East (Indo-European or Semitic, mainly). There have been attempts to link them to Minoans and Basque people, because they too spoke/speak a language that was/is not related to anything, but these attempts were not fruitful. Also the Etruscans did not settle in Umbria, they lived, believe it or not, in Etruria. My understanding is that they were hellenized when they were already in Italy, not before. I might be wrong, though.