He was one of the world's few remaining absolute monarchs. But King Abdullah's years as crown prince might have marked his legacy even more than his rule as king.
Abdullah bin Abdul-Aziz al-Saud became de facto ruler of the kingdom of Saudi Arabia in 1995 when his immediate predecessor, King Fahd, suffered a stroke. At the time, Abdullah was crown prince — but from that position he wielded a tremendous amount of power and influence.
Saudi state television reported his death on Thursday. He had been in the hospital for several weeks and had been suffering from pneumonia.
Saudi TV also announced that Crown Prince Salman bin Abdul-Aziz al-Saud, 79, is the new Saudi king and Prince Muqrin bin Abdul-Aziz is the new crown prince.
Abdullah was known to foreign diplomats as devout and conservative, with strong ties to the country's Bedouin tribes. But even then, he pushed for change in the kingdom. And when he finally ascended to the throne in 2005, many saw him as a beacon of hope for reform on a broad scale in Saudi Arabia. During his time as crown prince he promoted greater openness in two particular areas: the role of women and freedom of expression, and for a time there was greater tolerance of some degree of criticism of government policy.
On assuming the throne, Abdullah faced pressure from conservative clerics to restrain his reform program, aimed at bringing together Islamic traditions with the needs of a modern state. As monarch, he worked to trim the high-spending habits of the kingdom’s vast royal family and sought to tackle youth unemployment by liberalizing the economy and stimulating the private sector.
He paved the way for municipal elections, granted women the right to vote and run for office and issued them ID cards, allowing them for the first time to do business without the involvement of a male guardian.
Abdullah's other major decision was to set up a council of royal elders to make the royal succession more orderly. But domestic concerns gave way to global ones when the United States was attacked on Sept. 11, 2001. Fifteen of the 19 Al-Qaeda hijackers were Saudi citizens.
He took on Al-Qaeda when the group began a campaign of bombings against Westerners in the kingdom and ordered the conservative clergy to stop preaching intolerance in schools and mosques.
Abdullah's next major challenge after Sept. 11 and Al-Qaeda was Iran. His foreign policy focused on efforts to contain what the Sunni monarchy saw as the increasing regional influence of the Shia-led government of Iran. The resulting cold war between the two countries was played out in Lebanon, Syria and elsewhere in the region.
When former Lebanese Prime Minister Rafiq Hariri, who had been a strong ally of Saudi Arabia, was assassinated in 2005, most of the international community blamed the Iranian-backed Syrian government.
The Iran factor also influenced Abdullah's stance toward the Arab Spring.
He seemed to support regime change in Libya and to be lukewarm toward the revolutions in Egypt, Tunisia and Yemen. By sending troops to support Bahrain's monarchy against protesters, he may have revealed Saudi fears of an Iranian-backed revolution next door.
But Saudi Arabia's cold war with Iran reached its peak in Syria.
While Iran clearly backed President Bashar al-Assad, Abdullah was one of the staunchest supporters of the Syrian rebels.
At home, despite hopes that he would usher in an era of reform, his record on human rights remained controversial. Many became disillusioned by what they saw as a failure to deliver on high expectations, even on such limited symbolic issues as allowing women the right to drive. Judicial reforms failed to fulfill expectations, and Sunni-Shia communal tensions escalated.
In recent years activists who demanded change through petitions ended up in jail, and political parties and public demonstrations were banned.
But as Arab uprisings raged elsewhere, he spent $130 billion on housing, jobs and other social benefits in a bid to win the hearts and minds of his subjects.
His calculation appears to have worked, because despite online calls for a day of rage to protest the lack of democracy, no anti-government protest movement of the type seen elsewhere ever took hold in the kingdom.
And the king remained a largely popular figure.
His critics believe he could have done more, given Saudi Arabia's vast oil wealth, to help his population. But if the stability of Saudi’s monarchy is under threat, it’s not from looming poverty or a possible uprising but from old age — and a potential succession problem.
The country has recently seen two crown princes die and now its king, Salman, who is poised to take over from Abdullah, is nearly 80. His deputy is Muqrin, a younger direct son of Saudi Arabia's founding father, King Abdul-Aziz. With Muqrin's appointment, the post of deputy crown prince was created, perhaps to reduce the probabilities of a succession crisis in the near future. But he is nearly 70.
The crown in Saudi Arabia passes among brothers before it goes to sons. In a few years the last eligible direct son of Abdul-Aziz will die or become incapacitated by age.
That will leave several dozen royal grandsons vying for the throne.
Abdullah created the Allegiance Council of royal elders created to prevent such a problem. Its first real test could be just around the corner.