Abdullah bin Abdulaziz al-Saud became King of Saudi Arabia on August 1, 2005, when his half-brother King Fahd died. Abdullah had been Crown Prince and acted as the de-facto regent and ruler after King Fahd was incapacitated by a major stroke in 1996.
Abdullah also served as First Deputy Prime Minister and Commander of the Saudi National Guard. He is one of 37 sons of King Abdulaziz bin Abdulrahman Al-Saud, the founder of modern Saudi Arabia.
Abdullah was born in Riyadh to Ibn Saud's eighth wife, Fahda, and received his early education that was in the Royal Court at the Princes' School from religious authorities and intellectuals. He was given the position of Commander of the Saudi National Guard in 1963, and the position of First Deputy Prime Minister in June 1982.
Abdullah has four wives, seven sons and fifteen daughters.
Prince Abdullah has established two libraries in the Muslim world, one in Riyadh (the King Abdulaziz Library) and another in Casablanca, Morocco.
In October 1976, as Abdullah was being groomed for greater responsibility in Riyadh, he was sent to the United States to meet with then-President Gerald Ford. He again travelled to the United States in October 1987, meeting then-Vice President George H. W. Bush. In September of 1998, Abdullah made a state visit to the United States to meet in Washington, DC with then-President Bill Clinton. He returned again in September of 2000 to attend millennium celebrations at the United Nations in New York, New York. Abdullah is the fourth richest man in the world.
Since then Abdullah has visited America many times, and there are reports that the Bush family, including President George W. Bush consider Abdullah to be a great friend both of America and the Bush family.
Shortly after the September 11, 2001, terrorist attack on the United States, as criticism of Saudi Arabia mounted, Abdullah said, “The vicious campaign being waged against the kingdom in the Western media is nothing but the manifestation of a deep-rooted hatred directed against the course of Islam. Commitment to Islam and the homeland is not up for debate.” 
On the second anniversary of the September 11 attack on the United States, the prince wrote a letter to U.S. President George W. Bush, which ended with:
"God Almighty, in His wisdom, tests the faithful by allowing such calamities to happen. But He, in His mercy, also provides us with the will and determination, generated by faith, to enable us to transform such tragedies into great achievements, and crises that seem debilitating are transformed into opportunities for the advancement of humanity. I only hope that, with your cooperation and leadership, a new world will emerge out of the rubble of the World Trade Center: a world that is blessed by the virtues of freedom, peace, prosperity and harmony." 
In 2002, Abdullah floated the so-called Arab Peace Initiative, what many considered at the time to be an opening salvo in a Saudi attempt to make peace with Israel. The plan called for Israel to cede almost the entirety of the Occupied Territories to the Palestinian Authority and to recognize the PA's sovereignty, with the Authority's capital in East Jerusalem. In exchange, Abdullah offered unprecedented consessions, including the ending of the Arab-Israeli conflict, a peace treaty with Israel, recognition of the state of Israel and the establishment of "normal relations" between Arab states and Israel.
The plan was dropped after criticism from both Arab states and Israel.
Prince Abdullah is a devout Muslim and is said to have meetings with leaders of Saudi Arabia's religious establishment on a weekly basis to garner advice and guidance.
Like many Saudi rulers before him, Abdullah is considered by many in the West to be a relatively moderate ruler. In recent years, this image has been compromised however, as Saudi Arabian schools continue to teach anti-Semitism and Saudi Arabia's Royal Family funds madrassahs around the world that offer no compromise regarding the West's support and lack of support of Palestinian people. Saudi Arabia was also a major backer of the Taliban in Afghanistan. After the September 11, 2001, attacks, Saudi Arabia and the United Arab Emirates withdrew recognition of the Taliban government.
Abdullah bin Abdulaziz al-Saud died of natural causes at the age of 90 in his home on January 22 2014. His slightly younger, 79 year old brother Prince Salman bin Abdulaziz is expected to take his place.