Treaty of Saigon
By 1862, the war was over and in the Treaty of Saigon Vietnam was forced to concede the three provinces in the south, which became the colony of French Cochinchina. The subsequent 1863 Treaty of Huế also saw the Vietnamese Empire open three ports to French trade, allowed free passage of French warships to Kampuchea (which led to the French protectorate of Kampuchea), allowed freedom for French missionaries, and gave France a large indemnity for the cost of the war. France did not intervene in the Christian-supported Vietnamese rebellion in Bắc Bộ (despite missionary urging) or the subsequent massacre of thousands of Christians after the rebellion, suggesting that persecution of Christians prompted the original intervention but military and political reasons drove continued colonization of Vietnam.