Complex sentence: Although Longchamp regained the office of Chancellor after Richard's return to England he lost much of his former power, but he did retain Richard's trust, and was employed by the King until the bishop's death in 1197.
Split into simpler sentences: Although Longchamp regained the office of Chancellor after Richard's return to England, he lost much of his former power. He did, however, retain Richard's trust, and was employed by the King until the bishop's death in 1197.