Laos= landlocked peripheral country, was a French colony from the late 1800s and then client state, not super viciously fought over but just bombed a lot until the end of the Second Indochina War in 1975, when the Pathet Lao made socialism the law of the land.

Nepal= landlocked yet somewhat less peripheral country, never colonized but was a British client state from the early 19th century to the early 20th century, had active Marxist armed rebellions for decades that culminated in the abolition of the monarchy, now is a parliamentary democracy with strong Marxist parties.

Sri Lanka= rather important spice and maritime country, colonized to escalating degrees by the Portuguese, the Dutch, and the English, won independence peacefully from Britain and in the 70s became democratic socialist in name.