At independence, Greece had an area of 47,515 square kilometers (18,346 square mi.), and its northern boundary extended from the Gulf of Volos to the Gulf of Arta. Under the influence of the "Megali Idea," the expansion of the Greek state to include all areas of Greek population, Greece acquired the Ionian islands in 1864; Thessaly and part of Epirus in 1881; Macedonia, Crete, Epirus, and the Aegean islands in 1913; Western Thrace in 1918; and the Dodecanese islands in 1947.

Greece entered World War I in 1917 on the side of the Allies. After the war, Greece took part in the Allied occupation of Turkey, where many Greeks still lived. In 1921, the Greek army marched toward Ankara, but was defeated by Turkish forces led by Ataturk and forced to withdraw. In a forced exchange of populations, more than 1.3 million refugees from Turkey poured into Greece, creating enormous challenges for the Greek economy and society.

Greek politics, particularly between the two world wars, involved a struggle for power between monarchists and republicans. Greece was proclaimed a republic in 1924, but George II returned to the throne in 1935. A plebiscite in 1946 upheld the monarchy, which was finally abolished by referendum on December 8, 1974.

Greece's entry into World War II was precipitated by the Italian invasion on October 28, 1940. Despite Italian superiority in numbers and equipment, determined Greek defenders drove the invaders back into Albania. Hitler was forced to divert German troops to protect his southern flank and overran Greece in 1941. Following a very severe German occupation in which many Greeks died (including over 90% of Greeceís Jewish community) German forces withdrew in October 1944, and the government-in-exile returned to Athens.

After the German withdrawal, the principal Greek resistance movement, which was controlled by the communists, refused to disarm. A banned demonstration by resistance forces in Athens in December 1944 ended in battles with Greek Government and British forces. Continuing tensions led to the outbreak of full-fledged civil war in 1946. First the United Kingdom and later the U.S. gave extensive military and economic aid to the Greek Government. In 1947, Secretary of State George C. Marshall implemented the Marshall Plan under President Truman, which focused on the economic recovery and the rebuilding of Europe. The U.S. contributed hundreds of millions of dollars to rebuilding Greece in terms of buildings, agriculture, and industry.

In August 1949, the Greek national army forced the remaining insurgents to surrender or flee to Greece's communist neighbors. The insurgency resulted in 100,000 killed, 700,000 displaced persons inside the country, and catastrophic economic disruption. This civil war left Greek society deeply divided between leftists and rightists.

Greece became a member of NATO in 1952. From 1952 to late 1963, Greece was governed by conservative parties--the Greek Rally of Marshal Alexandros Papagos and its successor, the National Radical Union (ERE) of the late Constantine Karamanlis. In 1963, the Center Union Party of George Papandreou was elected and governed until July 1965. It was followed by a succession of unstable coalition governments.

On April 21, 1967, just before scheduled elections, a group of colonels led by Col. George Papadopoulos seized power in a coup d'etat. The junta suppressed civil liberties, established special military courts, and dissolved political parties. Several thousand political opponents were imprisoned or exiled to remote Greek islands. In November 1973, following an uprising of students at the Athens Polytechnic University, Gen. Dimitrios Ioannides replaced Papadopoulos and tried to continue the dictatorship.

Gen. Ioannides' attempt in July 1974 to overthrow Archbishop Makarios, the President of Cyprus, brought Greece to the brink of war with Turkey, which invaded Cyprus and occupied part of the island. Senior Greek military officers then withdrew their support from the junta, which toppled. Leading citizens persuaded Karamanlis to return from exile in France to establish a government of national unity until elections could be held. Karamanlis' newly organized party, New Democracy (ND), won elections held in November 1974, and he became Prime Minister.

Following the 1974 referendum, the Parliament approved a new constitution and elected Constantine Tsatsos as president of the republic. In the parliamentary elections of 1977, New Democracy again won a majority of seats. In May 1980, the late Prime Minister Karamanlis was elected to succeed Tsatsos as president. George Rallis was then chosen party leader and succeeded Karamanlis as Prime Minister.

On January 1, 1981, Greece became the 10th member of the European Community (now the European Union). In parliamentary elections held on October 18, 1981, Greece elected its first socialist government, the Panhellenic Socialist Movement (PASOK), led by Andreas Papandreou. In 1985, Supreme Court Justice Christos Sartzetakis was elected president by the Greek parliament. PASOK under Papandreou was re-elected in 1985.

Greece had two rounds of parliamentary elections in 1989; both produced weak coalition governments with limited mandates. In the April 1990 election, ND won 150 seats and subsequently gained 2 others. After Prime Minister Mitsotakis fired Foreign Minister Andonis Samaras in 1992, the rift led to the collapse of the ND government and a victory in the September 1993 elections for Andreas Papandreou's PASOK.

On January 17, 1996, following a protracted illness, Prime Minister Papandreou resigned and was replaced by former Minister of Industry Constantine Simitis. In elections held in September 1996, Constantine Simitis was elected prime minister. In April 2000, Simitis and PASOK won again, gaining 158 seats to ND's 125. Most recently, parliamentary elections were held March 8, 2004 and ND won 165 seats to PASOKís 117; Konstantinos Karamanlis, ND leader and the nephew of the former prime minister, became prime minister. Karolos Papoulias was elected President by Parliament in February 2005.

Greece's exemplary success in hosting a safe and secure 2004 Summer Olympics in Athens has enhanced its international prestige. The 2004 Olympics and Paralympics left an impressive and expensive legacy of new roads, spectacular stadiums, and modern public transportation systems, which the PASOK government began in 1997 and the New Democracy government of Karamanlis completed in 2004.