Diogenes Laertius Vitae philosophorum 8.1.1

[1] Having now completed our account of the philosophy of Ionia starting with Thales, as well as of its chief representatives, let us proceed to examine the philosophy of Italy, which was started by Pythagoras, ¹ son of the gem-engraver Mnesarchus, and according to Hermippus, a Samian, or, according to Aristoxenus, a Tyrrhenian from one of those islands which the Athenians held after clearing them of their Tyrrhenian inhabitants. Some indeed say that he was descended through Euthyphro, Hippasus and Marmacus from Cleonymus, who was exiled from Phlius, and that, as Marmacus lived in Samos, so Pythagoras was called a Samian.