Otto IV, Holy Roman Emperor was born in 1175 and became the first German king from the Welf dynasty. He was crowned Emperor in 1209, during a time of political turmoil in the Holy Roman Empire. Otto IV sought to strengthen imperial authority and expand his influence across Europe. His reign was marked by conflicts with rival factions, including the Hohenstaufen dynasty. Otto IV's ambitions led to a struggle for power, particularly with Philip of Swabia. Ultimately, his reign ended in 1215 when he was defeated, and he lost support, leading to his excommunication and the decline of his power.