Laos is a single-party socialist republic. It espouses Marxism and is governed by a single party communist politburo dominated by military generals. The Socialist Republic of Vietnam and the Vietnam People's Army continue to have significant influence in Laos. The capital city is Vientiane. Other large cities include Luang Prabang, Savannakhet, and Pakse. The official language is Lao. Laos is a multi-ethnic country with the politically and culturally dominant Lao people making up approximately 60% of the population, mostly in the lowlands. Mon-Khmer groups, the Hmong, and other indigenous hill tribes, accounting for 40% of the population, live in the foothills and mountains.