Tom Cullen (born 17 July 1985) is a Welsh actor. He had roles in the independent film Weekend (2011), as Anthony Foyle, Viscount Gillingham in the television series Downton Abbey, and as Sir Landry in the historical drama series Knightfall.
Cullen was born in Aberystwyth. His father is Irish and his mother is English. He spent his early years in Llandrindod Wells and moved to Cardiff at age 18, where he attended Llanishen High School. He is the son of two writers and has two siblings. Before pursuing an acting career he was involved in music. He graduated from the Royal Welsh College of Music and Drama in 2009 with First Class Honours degree in Acting after spending a year at the Central School of Speech and Drama.
Whilst still in training, Cullen was taken out of the Royal Welsh College of Music and Drama to appear in Daddy's Girl, which won the BAFTA Cymru for Best Film, and to star in Watch Me, which won the BAFTA Cymru for Best Short. His stage roles include Gorgio at the Bristol Old Vic, Assembly and A Good Night Out in the Valleys at National Theatre Wales, and The Sanger at Sherman Cymru. In 2011, he was named on the Screen International Stars of Tomorrow list.