Katheryn Winnick (born December 17, 1977) is a Canadian actress. She is best known for her roles in Amusement (2008), Bones (2010), A Glimpse Inside the Mind of Charles Swan III (2012), Vikings (2013–present), and The Art of the Steal (2013).
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. By age 21, she had started three martial arts schools.
Winnick has appeared in many films, including Stand Up Guys, Failure to Launch, Love & Other Drugs, and Killers. She has 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, Person of Interest, 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 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, starring in the role of Lagertha, a legendary figure in Viking history. In July 2017, Winnick stated on her Twitter account that she had been cast for a role in what was thought to be a film project, and that it will be announced at the SDCC. It was later revealed that she was cast as a main character in the Nazi Zombies mode of the video game Call of Duty: WWII.