Cambodia, in the view of the government in Paris, is a promising backwater.

Persuaded by a missionary envoy to seek French protection against both the Thai and the Vietnamese, King Ang Duong invites a French diplomatic mission to visit his court.

The Thai, however, pressure him to refuse to meet with the French when they finally arrive at Odongk in 1856.

The much-publicized travels of the naturalist Henri Mouhot, who visits the Cambodian court, rediscoversthe ruins at Angkor, and journeys up the Mekong River to the Laotian kingdom of Luang Prabang from 1859 to 1861, piques French interest in the kingdom's alleged vast riches and in the value of the Mekong as a gateway to China's southwestern provinces.

In August 1863, the French conclude a treaty with Ang Duong's successor, Norodom (1859-1904).

This agreement affords the Cambodian monarch French protection (in the form of a French official called a resident) in exchange for giving the French rights to explore and to exploit the kingdom's mineral and forest resources.