Among the fifty most populous nations in the world, the only two countries in which only two political parties are represented in the nation’s legislative lower house are the United States and Nigeria. If “two-party system” is defined to mean a nation with only two parties represented in the national legislature, then it is clear that the “two-party system” has been rejected by governments and voters all over the world.
Among the fifty most populous countries, only one country bans all political parties and holds no legislative elections whatsoever: Saudi Arabia. Only one of the fifty most populous countries has non-partisan elections for the national legislature: Iran. Although political parties, both legal and illegal, exist in Iran, the election system is non-partisan.
Two countries ban all political parties except the ruling party: China and Vietnam. The May 1 2015 printed Ballot Access News will have a chart showing the number of parties represented in each country’s lower legislative body, although the chart will only include the 50 most populous countries.