The Arab rebellion that occurred in Palestine from 1936 to 1939 led to additional measures to strengthen the legion, which on the eve of World War II consisted of about 1,350 officers and men. One thousand of these troops were organized for police duties and the remaining 350 made up the Desert MobileÍÍÍÍ Force, which then comprised two mechanized cavalry companies, having as its mission the prevention of Arab rebel incursions from Palestine.

Although the Arab Legion saw little action in the war, the mobile force became part of the tiny British columns that marched against Iraq and the Vichy French in Syria and Lebanon in 1941. It established an excellent record that prompted its expansion to a mechanized infantry brigade but, by the time this unit was ready for action, the war in the desert was over. The Arab Legion was subsequently detailed to strategic guard duties as individual companies throughout the Middle East. These operations provided experience that was to prove valuable when Arab-Israeli difficulties erupted in the postwar era. By the end of the war, the legion had expanded to a force of about 8,000, but postwar economy measures reduced its size to 6,000 by May 1948, when the British gave up their Palestine Mandate. At the same time, the TJFF was disbanded, and many members of the unit were absorbed into the legion.

About 4,500 legionnaires were combat troops at the time the Arab-Israeli War began in 1948. Moving across the Jordan River, the legion occupied most of the West Bank and assumed control of the strategic Jerusalem-Tel Aviv highway. Commanded by Glubb and about forty British officers, the legion fought better than any other Arab force and held its positions longer when Israel took the offensive in January 1949. The fighting left the legion in occupation of the Old City of Jerusalem and much of the Arab areas of Palestine that made up the West Bank.

During the 1948 war, the legion's strength was expanded hurriedly to approximately 8,000. As a consequence of the British withdrawal, for the first time the legion had to develop its own technical support services. A small air force unit was created for logistics, reconnaissance, and liaison purposes, then enlarged in 1955 to include a modest combat element (see Air Force , this ch.). By early 1956, when Hussein dismissed Glubb as commander of the military establishment, the legion had grown to about 23,000 officers and men. After Glubb's departure it was redesignated the Jordan Arab Army, and the national police element of about 6,000 was shifted from the military to be brought under the supervision of the minister of interior.

Between 1951 and 1956 an entirely new National Guard was formed, originally consisting merely of armed Palestinians in villages of the West Bank vulnerable to Israeli raids. It was later built up within Jordan proper by a conscription system, forming a territorial reserve army. Guardsmen, predominantly Palestinians, were unpaid except for a small wage during their annual training period under officers and noncomm 3ddissioneded officers (NCOs) of the legion. In 1965 the National Guard, by then a force of 30,000, was disbanded because of its unreliability and susceptibility to PLO influence. About 40 percent of these troops, after passing careful screening for loyalty to the monarchy, were allowed to join the Jordan Arab Army.

Although Jordan had signed a tripartite military treaty with Egypt and Syria in October 1956, a few days before Israel's attack on Egypt in the Sinai Peninsula, the conflict was confined to the Egyptian front. Israeli troops were positioned along the borders with Syria and Jordan in the event that these countries joined the fighting, but the alliance was not invoked.

Data as of December 1989