The Greek War of Independence began in 1821 and concluded in 1830 when England, France, and Russia forced the Ottoman Empire to grant Greece its independence under a European monarch, Bavarian prince Otto. He was deposed 30 years later, and the Great Powers chose a prince of the Danish House of Glucksberg as his successor. He became George I, King of the Hellenes.
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 "Meagali Idea," of expanding 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 Mustafa Kemal (later Ataturk) and forced to withdraw. In a forced exchange of populations, more than 1.3 million Christian 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. 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 millions of dollars to rebuilding Greece in terms of buildings, agriculture, and industry.
In August 1949, the 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 deep political division in Greek society between leftist and rightist.
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 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. Civil liberties were suppressed, special military courts were established, and political parties were dissolved. 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, which resulted in the rejection of the monarchy, a new constitution was approved by parliament on June 19, 1975, and parliament 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, 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 when the Panhellenic Socialist Movement (PASOK), led by Andreas Papandreou, won 172 of 300 seats. In 1985, Supreme Court Justice Christos Sartzetakis was elected president by the Greek parliament.
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 Mitsotakis fired his Foreign Minister, Andonis Samaras in 1992, the rift led to the collapse of the ND government and new elections in September 1993 won again by Andreas Papandreou's PASOK.
On January 17, 1996, following a protracted illness, Prime Minister Papandreou resigned and was replaced as Prime Minister 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 by a narrow margin, gaining 158 seats to ND's 125. Parliamentary elections were held March 8, 2004; Konstantinos Karamanlis became Prime Minister. Greece has suffered a severe economic crisis since late 2009, due to nearly a decade of chronic overspending and structural rigidities. Beginning in 2010, Greece entered three bailout agreements - with the European Commission, the European Central Bank (ECB), the IMF, and the third in 2015 with the European Stability Mechanism (ESM) - worth in total about $300 billion. The Greek Government formally exited the third bailout in August 2018.