Bulgaria changed systems of government.
Bulgaria . The Russo-Turkish War of 1877 -- 78 led to the formation of the Third Bulgarian State . In December 1989 the ruling Communist Party allowed multi-party elections , which subsequently led to Bulgaria 's transition into a democracy and a market-based economy . In a parliamentary system of government , a hung parliament is an expression used to describe a state of a parliament when no single political party ( or bloc of allied parties ) has an absolute majority of seats in the parliament ( legislature ) .