This war was part of the Arab-Israeli conflict, a conflict which has included many battles and wars since 1948. During the Six-Day War six years earlier, the Israelis had captured the Sinai clear to the Suez Canal, which had become the cease-fire line. The Israelis had also captured roughly half of the Golan Heights from Syria.

In the years following that war, Israel erected lines of fortification in both the Sinai and the Golan Heights. In 1971 Israel spent $500 million fortifying its positions on the Suez Canal, a chain of fortifications and gigantic earthworks known as the Bar Lev Line, named after Israeli General Chaim Bar-Lev.

Nonetheless, according to Chaim Herzog,

On June 19, 1967, the National Unity Government [of Israel] voted unanimously to return the Sinai to Egypt and the Golan Heights to Syria in return for peace agreements. The Golans would have to be demilitarized and special arrangement would be negotiated for the Straits of Tiran. The government also resolved to open negotiations with King Hussein of Jordan regarding the Eastern border.[3]

The Israeli decision was to be conveyed to the Arab nations by the United States. The US was informed of the decision, but not that it was to transmit it. There is no evidence of receipt from Egypt or Syria, who thus apparently never received the offer. The decision was kept a closely-guarded secret within Israeli government circles and the offer was withdrawn in October, 1967.[4]

Egypt and Syria both desired a return of the land lost in the Six-Day War. However, the Khartoum Arab Summit issued the "three nos," resolving that there would be "no peace, no recognition and no negotiation with Israel."

President Gamal Abdel Nasser of Egypt died in September 1970. He was succeeded by Anwar Sadat, who resolved to fight Israel and win back the territory lost in the Six-Day War. In 1971, Sadat, in response to an initiative by UN intermediary Gunnar Jarring, declared that if Israel committed itself to "withdrawal of its armed forces from Sinai and the Gaza Strip" and to implementation of other provisions of UN Security Council Resolution 242 as requested by Jarring, Egypt would then "be ready to enter into a peace agreement with Israel." Israel responded that it would not withdraw to the pre-June 5, 1967 lines.[5]

Sadat hoped that by inflicting even a limited defeat on the Israelis, the status quo could be altered. Hafiz al-Assad, the head of Syria, had a different view. He had little interest in negotiation and felt the retaking of the Golan Heights would be a purely military option. Since the Six-Day War, Assad had launched a massive military build up and hoped to make Syria the dominant military power of the Arab states. With the aid of Egypt, Assad felt that his new army could win convincingly against the Israeli army and thus secure Syria's role in the region. Assad only saw negotiations beginning once the Golan Heights had been retaken by force, which would induce Israel to give up the West Bank and Gaza, and make other concessions.

Sadat also had important domestic concerns in wanting war. "The three years since Sadat had taken office… were the most demoralized in Egyptian history… A desiccated economy added to the nation's despondency. War was a desperate option." (Rabinovich, 13). In his biography of Sadat, Raphael Israeli argued that Sadat felt the root of the problem was in the great shame over the Six-Day War, and before any reforms could be introduced he felt that shame had to be overcome. Egypt's economy was in shambles, but Sadat knew that the deep reforms that he felt were needed would be deeply unpopular among parts of the population. A military victory would give him the popularity he needed to make changes. A portion of the Egyptian population, most prominently university students who launched wide protests, strongly desired a war to reclaim the Sinai and was highly upset that Sadat had not launched one in his first three years in office.

The other Arab states showed much more reluctance to fully commit to a new war. King Hussein of Jordan feared another major loss of territory as had occurred in the Six-Day War, during which Jordan was halved in population. Sadat was also backing the claim of the PLO to the territories (West Bank and Gaza) and in the event of a victory promised Yasser Arafat that he would be given control of them. Hussein still saw the West Bank as part of Jordan and wanted it restored to his kingdom. Moreover, during the Black September crisis of 1970 a near civil war had broken out between the PLO and the Jordanian government. In that war Syria had intervened militarily on the side of the PLO, leaving Assad and Hussein estranged.

Iraq and Syria also had strained relations, and the Iraqis refused to join the initial offensive. Lebanon, which shared a border with Israel, was not expected to join the Arab war effort due to its small army and already evident instability. The months before the war saw Sadat engage in a diplomatic offensive to try to win support for the war. By the fall of 1973 he claimed the backing of more than a hundred states. These were most of the countries of the Arab League, Non-Aligned Movement, and Organization of African Unity. Sadat had also worked to curry favour in Europe and had some success before the war. Britain and France had for the first time sided with the Arab powers against Israel on the United Nations Security Council. In the run-up to the war, West Germany became one of Egypt's largest sources of materiel.

Events leading up to the war
Anwar Sadat in 1972 publicly stated that Egypt was committed to going to war with Israel, and that they were prepared to "sacrifice one million Egyptian soldiers." From the end of 1972, Egypt began a concentrated effort to build up its forces, receiving MiG-21s, SA-2, SA-3, SA-6 and SA-7 Surface-to-air missiles (SAM), RPG-7s, T-55 and T-62 Tanks, and especially the AT-3 Sagger anti-tank guided missile from the Soviet Union and improving its military tactics. Political generals, who had in large part been responsible for the rout in 1967, were replaced with competent ones.

The role of the great powers, too, was a major factor in the outcome of the two wars. The policy of the Soviet Union was one of the causes of Egypt's military weakness. President Nasser was only able to obtain the material for an anti-aircraft missile defense wall after visiting Moscow and pleading with the Kremlin leaders. He claimed that if supplies were not given, he would have to return to Egypt and tell the Egyptian people Moscow had abandoned them, and then relinquish power to one of his peers who would be able to deal with the Americans. The Americans would then have the upper hand in the region, which Moscow could not permit.

One of Egypt's undeclared objectives of the War of Attrition was to force the Soviet Union to supply Egypt with more advanced arms and war materiel. Egypt felt the only way to convince the Soviet leaders of the deficiencies of most of the aircraft and air defense weaponry supplied to Egypt following 1967 was to put the Soviet weapons to the test against the advanced weaponry the United States supplied to Israel.

Nasser's policy following the 1967 defeat conflicted with that of the Soviet Union. The Soviets sought to avoid a new conflagration between the Arabs and Israelis so as not to be drawn into a confrontation with the United States. The reality of the situation became apparent when the superpowers met in Oslo and agreed to maintain the status quo. This was unacceptable to Egyptian leaders, and when it was discovered that the Egyptian preparations for crossing the canal were being leaked, it became imperative to expel the Russians from Egypt. In July 1972 Sadat expelled almost all of the 20,000 Soviet military advisors in the country and reoriented the country's foreign policy to be more favorable to the United States.

The Soviets thought little of Sadat's chances in any war. They warned that any attempt to cross the heavily fortified Suez would incur massive losses. The Soviets, who were then pursuing détente, had no interest in seeing the Middle East destabilized. In a June 1973 meeting with U.S. President Richard Nixon, Soviet leader Leonid Brezhnev had proposed Israel pull back to its 1967 border. Brezhnev said that if Israel did not, "we will have difficulty keeping the military situation from flaring up"—an indication that the Soviet Union had been unable to restrain Sadat's plans (Rabinovich, 39).

In an interview published in Newsweek (April 9, 1973), President Sadat again threatened war with Israel. Several times during 1973, Arab forces conducted large-scale exercises that put the Israeli military on the highest level of alert, only to be recalled a few days later. The Israeli leadership already believed that if an attack took place, the Israeli Air Force would be able to repel it.

Almost a full year before the war, in an October 24, 1972, meeting with his Supreme Council of the Armed Forces, Sadat declared his intention to go to war with Israel even without proper Soviet support (Rabinovich, 25). Planning was done in absolute secrecy—even the upper-echelon commanders were not told of war plans until less than a week prior to the attack, and the soldiers were not told until a few hours beforehand. The plan to attack Israel in concert with Syria was code-named Operation Badr (the Arabic word for "full moon").