Though Clark tried to maintain peaceful relations with indigenous nations and negotiated peace treaties, he was involved in President Andrew Jackson's Indian removal policy. This included "his duty to oversee removal". He managed retaliation against Black Hawk and those allied with him in the Black Hawk War, when hostilities arose between them and the Americans. Clark issued "an extermination order", which he gave to Lewis Cass, a man who played a central role in Jackson's removal policy.