The armed forces of Iraq as a modern country began to be formed by the British after they assumed mandated control over Iraq after 1917. During the March 1921 Cairo conference, it was agreed that an Iraqi Army would be created along British lines, with training and equipment provided by the UK. King Faisal wanted an army of 15,000–20,000 men. The army actually grew from 3,500 in 1922 to 7,000 in 1927 and then to 11,500 in 1932. The army became a modernising influence in the country. In 1931, the Iraqi Air Force was founded with a small number of pilots. Six Army coups took place, with one in 1936 being led by Bakr Sidqi and the last being the Rashid Ali coup of 1941. Following the persecution of the Assyrians, which culminated in the Simele massacre of 1932, a conscription law was introduced, which strengthened the Iraqi Army at the expense of the tribal sheiks. In 1938–1939, Iraqi Army forces were concentrated near the Kuwaiti border, as the military portion of a policy by then-King Ghazni to encourage its union with Iraq. British forces later defeated the Iraqis in the short Anglo-Iraqi War of May 1941, during the Second World War. The Iraqi Air Force used British aircraft until the 14 July Revolution in 1958, where the new Iraqi government began increased diplomatic relationships with the Soviet Union. The Iraqi Air Force used both Soviet and British aircraft throughout the 1950s and 1960s. In 1961, Iraqi forces were again amassed along the Kuwaiti border, and Iraqi again threatened to invade. A quick British deployment of troops, aircraft, and naval vessels, called Operation Vantage, deterred any move though. Iraqi forces fought in the 1948 Arab–Israeli War, a first war against the Kurds from 1961 to 1970, and then in the Six-Day War of 1967.