Frederick I Barbarossa (1122 – 10 June 1190) is a German Holy Roman Emperor.

He is elected King of Germany at Frankfurt on 4 March 1152 and crowned in Aachen on 9 March as King of Italy in Pavia in 1155, and finally crowned Roman Emperor by Pope Adrian IV, on 18 June 1155.

Two years later in 115,7 the term "sacrum" (i.e.

"holy") first appears in a document in connection with his Empire.

He is then also formally crowned King of Burgundy at Arles on 30 June 1178.

The name Barbarossa comes from the northern Italian cities he attempts to rule, and means "red beard" in Italian – a mark of both their fear and respect.

In German, he is known as Kaiser Rotbart, which has the same meaning.

Before his royal election, he was by inheritance Duke of Swabia (1147–1152, as Frederick III).

He is the son of Duke Frederick II of the Hohenstaufen dynasty.

His mother is Judith, daughter of Henry IX, Duke of Bavaria, from the rival House of Welf, and Frederick therefore descendsfrom Germany's two leading families, making him an acceptable choice for the Empire's prince-electors.