Frederick I, also known as Frederick Barbarossa, was the Holy Roman Emperor from 1155 until his death in 1190. He was a member of the Hohenstaufen dynasty and is remembered for his efforts to consolidate the empire and strengthen imperial authority. Frederick sought to expand his influence in Italy, engaging in several military campaigns against the city-states and the Papacy. Frederick's reign was marked by his charismatic leadership and his commitment to the idea of a unified Christian empire. He participated in the Third Crusade but drowned in the Saleph River in 1190, leading to a decline in his ambitions and the fragmentation of the empire. His legacy includes the enduring image of a powerful emperor in medieval Europe.