Indochina is a region of Southeast Asia; most narrowly, it is the former French colonies of Vietnam, Cambodia and Laos, which were collectively known as French Indochina during the colonial period. However, it is sometimes considered to also include Thailand, which was never colonised, and Myanmar, a former British colony, both of which share many cultural similarities with the other three countries, which include the dominance of Buddhism as the main religion, as well as the relatively heavy use of fish sauce in the local cuisine. Peninsular Malaysia is sometimes included, but only rarely, as it does not share the same cultural similarities as the other five; a better term to include peninsular Malaysia would be mainland Southeast Asia.