Inspired by Henri Mouhot's account of the rediscovery of the ancient cities of Angkor in the Cambodian jungle, Thomson embarked on what would become the first of his major photographic expeditions. He set off in January 1866 with his translator H. G. Kennedy, a British Consular official in Bangkok, who saved Thomson's life when he contracted jungle fever en route. The pair spent two weeks at Angkor, where Thomson extensively documented the vast site, producing some of the earliest photographs of what is today a UNESCO World Heritage Site.