第6回十字軍
Otto impressed Honorius III on his mission of 1224 and he was recruited into the Papal chancery and appointed a Papal chaplain. By February 1225, he held the post of "auditor litterarum contradictarum", auditor of contradicting letters. Later that year, as a subdeacon, he was sent to England to raise funds for the Sixth Crusade. He left England before Easter 1226, having achieved little.