The anointment of the House of Saud more than three centuries ago came with a pledge to rule in tandem with the austere clerics of Wahhabi Islam whose puritanical theology has provided some of the underpinnings for extremist groups throughout the Middle East.

In Saudi Arabia, that partnership has left the royal family presiding over a deeply conservative society with one of the worst human rights records on earth.

Public beheadings routinely follow Friday prayers, drawing large crowds. And t his month, a Saudi blogger became the subject of an international campaign to save him from a sentence of 1,000 lashes spread over 20 weeks — a punishment so severe that doctors recommended that a second round of 50 lashes be postponed Friday because he had not healed from the first.

Wahhabi doctrine is so deeply entrenched in the desert kingdom that few believe King Salman — who took the throne Friday — is likely to make many reforms.

The grand bargain forged in 1774 between Mohammed ibn al Saud, then a minor clan leader, and the cleric Mohammed Abdul Wahhab provided the ideological justification for uniting under the rule of the House of Saud the tribes scattered across the Arabian Peninsula.

As their empire expanded, so did the influence of the Wahhabi clerics, who seek to convert Muslims to their “purer” form of Islam. Billions of dollars from the country’s oil earnings have been spent on spreading Wahhabism around the world.

Within the kingdom, the clergy broad power over education, justice, family law and the role of women . Yet tensions have emerged through the years, especially with the rise of al-Qaida and the Islamic State — extremist groups with roots in Wahhabism.

In the last decade, the country’s rulers have sought to moderate the sermons of some of the kingdom’s most radical clergy. More modern-thinking clerics have been promoted to senior state positions and scholars from other branches of Sunni Islam brought onto the top clerical council.

“The Wahhabis do not have the same grip over power in Saudi Arabia as they used to over the past centuries,” said Ammar Ali Hassan, a Cairo-based political analyst. “The power of politics has overtaken the influence of religion on governing the kingdom, and King Abdullah should be the one taking the credit.”

The late king, whom Salman succeeded, encouraged a re-evaluation of the status of women and the rights of religious minorities. He took steps to modernize education and aspects of the judicial system. And in 2013, he appointed 30 women to the Shura Council, a consultative body that produces recommendations for the Cabinet.

But the changes were modest. Women are still forbidden from accessing higher education, marrying, obtaining a passport or traveling without the approval of a male guardian. Two women were detained last month for trying to drive a car.

“It is not enough for women to sit on the Shura Council if they can’t even drive themselves to work,” said Joe Stork, deputy Middle East director at Human Rights Watch.

The spread of the Internet has provided an opening for Saudis to discuss sensitive social and political issues. But the government continues to punish those — like the blogger Raif Badawi — who criticize members of the royal family, senior clerics or government policies.

With the rapidly declining situation on the country’s borders with Yemen and Iraq, the new king could decide to fall back on the alliance with the clergy, said Middle East expert Jane Kinninmont — and that could bode ill for those seeking greater protections for women, religious minorities and peaceful dissent.