This was opposed by the Emperor Frederick Barbarossa.

The importance of the fortress was confirmed by Emperor Frederick Barbarossa's visit in 1185.

In 1186 Emperor Frederick Barbarossa put the monastery under Imperial protection.

Major operations did not begin until 1157 when Albert received troops and other support from Emperor Frederick Barbarossa.

He fled to Germany, asking Emperor Frederick Barbarossa for protection.

This ruling had been made at a meeting with the Emperor Frederick Barbarossa.

He was a nephew of Emperor Frederick Barbarossa and supported his policies.

In the church the Emperor Frederick Barbarossa was crowned in 1155.

The city was destroyed by Emperor Frederick Barbarossa in 1155, but was soon rebuilt.

Emperor Frederick Barbarossa took over the reins of power.