Samuel was born inHamilton, Victoria, the son of Maree and Clifford Samuel.He grew up inAdelaide, South Australia and graduated fromRostrevor Collegein 2001. He has a younger brother,Benedict, a writer, producer and actor,as well as an older sister, Bridget, a stage manager. Despite completing his senior secondary years atRostrevor College, Samuel undertook final year drama atChristian Brothers Collegeunder the tutelage of Amanda Portus, where he played the part of Tom Snout (the wall) in Rostrevor College's production ofShakespeare'sA Midsummer Night's Dreamas well as playing "Belvile" in CBC's production ofAphra Behn'sThe Rover(The Banished Cavaliers). Xavier Samuel later attended Flinders University Drama Centre in 2005, where he studied under renowned acting teacher Professor Julie Holledge. He playedHamletin the graduate production.