This text is largely taken from Wikipedia.
Faisal bin Hussein bin Ali al-Hashemi was born in Ta'if (in present-day Saudi Arabia) in 1883, the third son of Hussein bin Ali, the Grand Sharif of Mecca. He grew up in Istanbul and learned about leadership from his father. In 1913 he was elected to the Ottoman parliament as representative of the city of Jeddah.
After the start of the First World War, the Turks, who ruled over the Ottoman Empire, sided with the Germans. When it was discovered that the Turks were plotting to over throw the Sharif and replace him with a rival, Faisal, along with his father and brothers, devised a plan of an Arab revolt against the Turks. For this they needed help. Eventually, in October 1916, Faisal met the British intelligence officer T.E. Lawrence (later known as “Lawrence of Arabia”). The British were already planning to break up the Ottoman Empire for their own purposes after the war.
With the help of Lawrence, Faisal sided with the British army and organised the Arab revolt against the Ottoman Empire that helped to end the Caliphate. He also worked with the Allies in their conquest of Greater Syria and the capture of Damascus, where he became part of a new Arab government in 1918.
On 7 March 1920, Faisal was proclaimed King of Greater Syria by the Syrian National Congress government of Hashim al-Atassi. In April 1920, the San Remo conference gave France the mandate for Syria, which led to the Franco-Syrian War. In the Battle of Maysalun on 24 July 1920, the French were victorious and Faisal was expelled from Syria. He went to live in the United Kingdom in August of that year.
Meanwhile, the British government, mandate holders in Iraq, were concerned at the unrest in the colony. They decided to step back from direct administration and create a monarchy to head Iraq while they maintained the mandate. Following a rigged plebiscite showing 96% in favour, Faisal was made King of Iraq in August 1921.
As a pan-Arabist, and to cultivate better Iraqi-Syrian relations , Faisal encouraged an influx of Syrian exiles and office-seekers. This influx resulted in much native resentment towards Syrians and Lebanese in Iraq. Faisal also developed desert motor routes from Baghdad to Damascus, and Baghdad to Amman.
In 1932, the British mandate ended and Faisal was instrumental in making his country nominally independent. On 3 October, the Kingdom of Iraq joined the League of Nations. In July 1933, shortly before his death, Faisal went to London to ask the British to limit Jewish migration and land sales in Palestine. He died on September 8, 1933, of a heart attack while staying in Bern, Switzerland. He was succeeded on the throne by his oldest son Ghazi.