Battle of Bouvines
Dietrich brought a legal suit to be reinstated; the suit dragged on for three years. At the Battle of Bouvines, 27 July 1214, Dietrich's ally, Otto, was defeated. A year later Dietrich's suit was rejected. He retired to the deanery at the Apostles church, and died there after 1223. The Cathedral Chapter of Cologne paid the expenses on his lawsuit until 1238.