Frederick I was known as Frederick Barbarossa. It means "red beard" in Italian. Frederick was born in 1122 and became Duke of Swabia in 1147. He accompanied his uncle, Conrad III (King of Germany) to the Middle East during the Second Crusade. The expedition was a disaster, but Frederick served with distinction during the expedition and Conrad was impressed with his performance. When Conrad died in 1152, Frederick succeeded him as king. He pursued the crown of the Holy Roman Empire with a military campaign in Italy. In 1155 he was crowned Emperor in Rome by Pope Adrian IV, with the people of Rome rioting over his crowning. Frederick would conduct other campaigns in Italy throughout his reign. The term "Barbarossa" came from Northern Italian cities which he tried to rule, but they actively resisted his control.

Frederick's last campaign was the Third Crusade, organized with King Richard the Lionheart and French King Philip Augustus. Frederick's army traveled overland toward the Holy Land, passing through Hungary, Serbia and Bulgaria, reaching Constantinople in late 1189. In 1190, during a battle in Asia Minor (modern-day Turkey), at the Saleph river Frederick was thrown from his horse and fell into the river. He was wearing his armor and in the relatively shallow water, drowned. His death caused great panic among his men resulting in desertion and numerous deaths. Only a small portion of his army reached the Holy Land.

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