Frederick I Barbarossa ( 1122 â `` 10 June 1190 ) was elected King of Germany at Frankfurt on 4 March 1152 and crowned in Aachen on 9 March , crowned King of Italy at Pavia in 1154 , and finally crowned Holy Roman Emperor by Pope Adrian IV on 18 June 1155 . Frederick I Barbarossa ( 1122 -- 10 June 1190 ) was a German Holy Roman Emperor . He was elected King of Germany at Frankfurt on 4 March 1152 and crowned in Aachen on 9 March , crowned King of Italy in Pavia in 1155 , and finally crowned Roman Emperor by Pope Adrian IV , on 18 June 1155 , and two years later in 1157 the term `` sacrum '' ( i.e. `` holy '' ) first appeared in a document in connection with his Empire .