In 1978, the Vietnamese army invaded and seized Phnom Penh in 1979 and pushed the Khmer Rouge into the jungles, ending the genocide.

With the success of the Vietnamese invasion, a former Khmer Rouge leader, Heng Samrin, led a revolt against Pol Pot and took over as Cambodia’s President and Communist leader in 1979. Throughout the 1980s Cambodia civil war raged with fighting among Sihanouk-led guerrilla group, Heng Samrin army, Hun Sen army, Vietnamese troops and Pol Pot’s Khmer Rouge. Heng Samrin lost power to Hun Sen, the new Vietnamese-backed premier, but remained Head of State until Sihanouk’s return in 1991.

In 1987, peace talks among the warring leaders began in Paris, and in 1989, Vietnam agreed to withdraw all its troops. On Oct. 23, 1991, a Paris Peace treaty was signed by all the warring leaders: Sihanouk, Hun Sen and Pol Pot. However, the Khmer Rouge did not disarm as agreed and continued guerilla fighting.

Sihanouk criticized the Khmer Rouge and joined forces with Hun Sen to become Head of State again in 1991. The United Nations began working for democratic elections in Cambodia.

1993-1997 - Royal Government of Cambodia: The Beginning of Democracy
1998-2002 - Royal Government of Cambodia: Monarchy, National Assembly and Senate
2003-2007 - Cambodia Without a Government: The Deadlock

In May 1993, Cambodia held its first democratic elections, supervised by a large UN-peace keeping mission called UNTAC. Khmer Rouge boycotted the elections and continued to fight in the large territories they controlled in the northern and western parts of the country. Royalist party won the largest number of seats and Hun Sen’s party came in second. A two party coalition government was formed with co-premiers, Prince Norodom Ranariddh and Hun Sen, sharing powers. And a new constitution reestablished the monarchy and Sihanouk became King.

Royal Government of Cambodia has a constitutional monarchy headed by a king and a parliament headed by a premier. The parliament consists of a popularly elected National Assembly with at least 120 members and a Senate with no more than half the number of members of the National Assembly. Members of parliament serve five-year terms. The premier must have the support of two thirds of the members of the National Assembly.

In July 1998, Prince Ranariddh returned to Cambodia and ran against Hun Sen again in the legislative elections. Hun Sen's party (the Cambodian People's party) was the official winner of the controversial election and he became the only premier. Prince Ranariddh became the president of the National Assembly. Hun Sen has since further strengthened his control of the country.