A treaty is a formal agreement between Indigenous nations and the Crown (representing British or Canadian government) establishing relationships, sharing lands, and defining mutual rights and obligations. Historic treaties dating from before Confederation through the early 20th century cover much of Canada, though significant areas (particularly in BC and parts of Quebec) lack historic treaties. Modern comprehensive land claims agreements function as treaties. Treaties are constitutionally protected and create binding obligations on governments. Treaty interpretation has evolved—courts now require treaties be understood from Indigenous perspectives and interpreted to fulfil their spirit. Many Indigenous peoples view treaties as sacred agreements between nations, not merely legal contracts. Understanding treaties is fundamental to Indigenous-Canadian relations and reconciliation.