Frederick I , was the Holy Roman Emperor from 2 January 1155 until his death. He was elected King of Germany at Frankfurt on 4 March 1152 and crowned in Aachen on 9 March 1152. He was crowned King of Italy on 24 April 1155 in Pavia and Roman Emperor by Pope Adrian IV on 18 June 1155 in Rome. Two years later, the term sacrum first appeared in a document in connection with his Empire. He was later formally crowned King of Burgundy, at Arles on 30 June 1178. He was named Barbarossa by the northern Italian cities which he attempted to rule: Barbarossa means "red beard" in Italian; in German, he was known as Kaiser Rotbart, which has the same meaning.