Contact

The Corps of Discovery's pattern of contact with tribal leaders developed as they traveled. Their ritual shaped all later contact by United States representatives with the Plains, Plateau, Great Basin and Northwest tribes. They adopted some tribal traditions where appropriate, such as presenting gifts to show good faith and smoking the peace pipe to establish good will.

They established the practice of referring to the sitting president as the "great father." They presented Jefferson Peace Medals and American flags as a gesture of peace, but in fact their gifts had larger implications. Some of the tribes already had established trade agreements with the British. Lewis and Clark were the vanguard of an attempt by the United States to alter the balance of power and trade in the new territory. To impress tribal leaders, the co-commanders often demonstrated their weapons, including Lewis' nearly silent air rifle.