In the 18th century, a religious scholar of the central Najd, Muhammad bin Abdul Wahhab, joined forces with Muhammad bin Saud, the ruler of the town of Diriyah, to bring the Najd and the rest of Arabia back to the original and undefiled form of Islam.
The Kingdom of Saudi Arabia is the heartland of Islam, the birthplace of its history, the site of the two holy mosques and the focus of Islamic devotion and prayer. Saudi Arabia is committed to preserving the Islamic tradition in all areas of government and society. Islam guides not only the lives of the people, but also the policies and functions of the government. The Holy Qur'an is the constitution of the Kingdom and Shari'ah (Islamic law) is the basis of the Saudi legal system.
Saudi Arabia is a leader in the pursuit of worldwide Islamic solidarity. It hosts the Muslim World League and the Organization of the Islamic Conference, institutions dedicated to preserving Islamic interests.
In many respects, the Kingdom has been responsive to the needs of the Islamic world. Saudi Arabia contributes generously to the Islamic Development Fund, which provides assistance for community infrastructure projects; to the Islamic Development Bank, headquartered in Jeddah, and to the Islamic Organization for Science, Technology and Development. Saudi Arabian leaders also work tirelessly to promote peace and stability in Muslim and Arab countries and throughout the world.