The Vikings character of Ragnar Lothbrok is played by Travis Fimmel. From the History channel biography for this character Ragnar is listed as:
“A young Viking warrior and farmer, Ragnar believes he is destined for greatness. Frustrated by the restrictive policies of his local chieftain, Earl Haraldson, he is convinced that great riches lie to the west and resolves to sail across the ocean to find them. Ragnar identifies with the god Odin, who traded his eye for knowledge, and is endlessly curious about what lies beyond his homeland. He lives with his wife Lagertha, a respected warrior in her own right, and their two young children.”
Travis Fimmel is an Austrailian native and will be in the 2013 film with Billy Bob Thornton titled “The Baytown Outlaws”.