On September 23, 1952, the Chamber of Deputies elected Camille Shamun to succeed Khuri. In the spring of 1953, relations between President Shamun and Jumblatt deteriorated as Jumblatt criticized Shamun for accommodating himself to the traditional pattern of Lebanese politics and for toning down the radical ideals that had led to the change of government in 1952. The balance between religious communities, provided for in the National Pact, was precariously maintained, and undercurrents of hostility were discernible. The Muslim community criticized the regime in which Christians, alleging their numerical superiority, occupied the highest offices in the state and filled a disproportionate number of civil service positions. Accordingly, the Muslims asked for a census, which they were confident would prove their numerical superiority. The Christians refused unless the census were to include Lebanese emigrants who were mainly Christians, and they argued that Christians contributed 80 percent of the tax revenue.

The 1956-58 period brought many pressures to bear on Lebanon. First, there was general unrest in the Arab world following the Suez Canal crisis and the abortive attacks on Egypt by Britain, France, and Israel. More specifically, however, political struggles occurred in two fields: rivalry among Lebanese political leaders who were linked to religious or clan groups and their followers; and the ideological struggle causing polarization between Lebanese nationalism and growing pan-Arabism.

President Gamal Abdul Nasser of Egypt became the symbol of panArabism after the 1956 Suez crisis and the 1958 merger of Egypt with Syria to form the United Arab Republic. He had great influence on Lebanese Muslims, who looked to him for inspiration. In this period of unrest, the Lebanese authorities, most of whom were Christians, insisted on two things: maintaining the country's autonomy and cooperating with the West. Christians considered their friendly relations with the West as the only guarantee of Lebanon's independence. President Shamun's refusal to respond favorably to pan-Arab pressures was in direct opposition to the stand of several prominent Sunni leaders, who devoted themselves to Nasser and the pan-Arab cause.

In 1957 the question of the reelection of Shamun was added to these problems of ideological cleavage. In order to be reelected, the president needed to have the Constitution amended to permit a president to succeed himself. A constitutional amendment required a two-thirds vote by the Chamber of Deputies, so Shamun and his followers had to obtain a majority in the May-June 1957 elections.

Shamun's followers did obtain a solid majority in the elections, which the opposition considered "rigged," with the result that some non-Christian leaders with pan-Arab sympathies were not elected. Deprived of a legal platform from which to voice their political opinions, they sought to express them by extralegal means. The conflict between Shamun and the pan-Arab opposition gained in intensity when Syria merged with Egypt. Pro-Nasser demonstrations grew in number and in violence until a full-scale rebellion was underway. The unrest was intensified by the assassination of Nassib Matni, the Maronite anti-Shamun editor of At Talagraph, a daily newspaper known for its outspoken panArabism . The revolt almost became a religious conflict between Christians and Muslims.

This state of turmoil increased when, in the early hours of July 14, 1958, a revolution overthrew the monarchy in Iraq and the entire royal family was killed. In Lebanon jubilation prevailed in areas where anti-Shamun sentiment predominated, with radio stations announcing that the Shamun regime would be next. Shamun, realizing the gravity of his situation, summoned the ambassadors of the United States, Britain, and France on the morning of July 14. He requested immediate assistance, insisting that the independence of Lebanon was in jeopardy.

Furthermore, he invoked the terms of the Eisenhower Doctrine, which Lebanon had signed the year before. According to its terms the United States would "use armed forces to assist any [Middle East] nation . . . requesting assistance against armed aggression from any country controlled by international communism." Arguing that Lebanese Muslims were being helped by Syria, which had received arms from the Soviet Union, Shamun appealed for United States military intervention. The United States responded, in large measure because of concern over the situation in Iraq and the wish to reassure its allies, such as Iran and Turkey, that the United States could act. United States forces began arriving in Lebanon by mid-afternoon of July 15 and played a symbolic rather than an active role. In the course of the 1958 Civil War, in which United States forces were not involved, between 2,000 and 4,000 casualties occurred, primarily in the Muslim areas of Beirut and in Tripoli. At the end of the crisis, the Chamber of Deputies elected General Fuad Shihab, then commander in chief of the Lebanese Army, to serve as president.

Data as of December 1987