The armies of Louis and two of his sons met at Rotfeld, near Colmar, on 24 June 833. The sons persuaded Gregory to go to Louis's camp to negotiate, and initially Louis refused to treat Gregory with any honour. However, Gregory managed to convince Louis of his good faith, and returned to Lothair to arrange a peace. However, Gregory soon learned that he had been deceived by Lothair. Gregory was prevented from returning to the emperor, while Louis was deserted by his supporters and was forced to surrender unconditionally; Louis was deposed and humiliated at the Campus Mendacii, and Lothair was proclaimed emperor. Following these events, Gregory returned to Rome. A second fraternal quarrel resulted in Louis being restored in 834, but his position was sufficiently weakened that Lothair retained the Kingdom of Italy.