 A Scandinavian version of the story of Hamlet (called Amleth or Amlóði, which means "mad" or "not sane" in Old Norse) was put into writing around 1200 AD by Danish historian Saxo Grammaticus in his work "Gesta Danorum" (the first full history of Denmark).It is this work Shakespeare borrowed from to create "Hamlet".Similar accounts are found in the Icelandic "Saga of Hrolf Kraki" and the Roman legend of Lucius Junius Brutus, both of which feature heroes who pretend to be insane in order to get revenge.