Eugene m. Ancient Greek εὖ 'well' + Ancient Greek γένος 'race, stock, kin, family'.
The name of a 4th C saint, a 5th C prince of North Wales, a 7th C pope and saint, a 7th C Brittonic ruler, an 8th C Brittonic ruler, a 9th C pope, a 10th C king of Strathclyde, an 11th C king of Strathclyde, a 12th C pope, a 12th C king of Gwynedd, a 12th C prince of Powys, a 13th C king of Gwynedd, a 15th C prince of Wales, and a 15th C pope.
The name was adopted into Old Welsh as Ou(u)ein or Eug(u)ein; this was the name a 6th C son of a king of Rheged who became the basis for a knight of the Round Table and son of King Urien in Arthurian legend. The popularity of Arthurian legend cycles in France contributed to the use of Yvain, the Old French form of the name. In Ireland, the corresponding form was Eoghan. The connection between Owen and Eoghan on the one hand and Eugene on the other is sometimes disputed.