His activities included a long, but unsuccessful siege of Venice in 810.
After an unsuccessful siege at Diu, he decided to return.
In 1322 there was yet another unsuccessful Scottish siege.
The first, certainly still unsuccessful siege lasted from April 1362 until May 1363.
With depleted forces the war ended in an unsuccessful siege of Constantinople.
Another unsuccessful siege by the Turks followed in 1532.
Together with the Bulgarians, he then undertook an unsuccessful siege of the city in 1235-6.
After an unsuccessful siege of Ueckermünde, the two sides agreed to a cease-fire.
In 1247, he took part in the unsuccessful siege of Parma.
He also made an unsuccessful siege of the city of Fritzlar in 1232.
