Political unity came late to the Lau Islands. Historically, they comprised three territories: the Northern Lau Islands, the Southern Lau Islands, and the Moala Islands. Around 1855, the renegade Tongan prince Enele Ma'afu conquered the region and established a unified administration. Calling himself the "Tui Lau", or King of Lau, he promulgated a constitution and encouraged the establishment of Christian missions. The first missionaries had arrived at Lakeba in 1830, but had been expelled. The "Tui Nayau," who had been the nominal overlord of the Lau Islands, became subject to Ma'afu.