Katheryn Winnick, born Katerena Anna Vinitska, is a Canadian actress.
Winnick was born in Etobicoke, Ontario and is of Ukrainian descent. She spoke Ukrainian as her first language and did not begin speaking English until she was eight years old. She began training in martial arts at age seven, and obtained her first black belt at 13.
Winnick has appeared in many films, including Stand Up Guys, Failure to Launch, Love and Other Drugs, and Killers. She has also guest starred in numerous television shows, most notably House, The Glades, Bones, Law & Order, Law & Order: Criminal Intent, CSI, CSI: NY, CSI: Miami, Criminal Minds, and Nikita. In her role on Bones, she portrays Hannah Burley, a war correspondent who had been posted to cover the war in Afghanistan and eventually becomes a love interest for main character Seeley Booth.
Winnick starred in the comedy-drama film Cold Souls, which had its world premiere at the Sundance Film Festival 2009. In 2011, Winnick was cast in a guest role on The CW's spy drama Nikita. In 2013, she starred in A Glimpse Inside the Mind of Charles Swan III and appeared in the comedy The Art of the Steal. She also joined History Channel's Vikings in the role of Lagertha, a legendary figure in Viking history.