Briefly Crown Prince from 1964 to 1965, he was among the wealthiest and most powerful members of the Saudi royal family. His advice was sought and deferred to in all matters by his brothers. Until his death in 1988, he was a close and powerful confidant and senior adviser to his younger brothers, King Khalid and King Fahd.

Prince Muhammad was born in 1910 and is the fourth son of King Abdulaziz. However, his birth date is also given as 1909, and William A. Eddy reports that he is the third son of King Abdulaziz.

His mother, Al Jawhara bint Musaed Al Jiluwi, was from the important Al Jiluwis, a clan whose members intermarried with the members of Al Saud family.King Khalid was his full brother, his full sister, Al Anoud, married the sons of Saad bin Abdul Rahman. She first married Saud bin Saad. After Saud died, she married Fahd bin Saad.

Prince Muhammad and Prince Faisal were given the responsibility for the Ikhwan in mid-1920s. Prince Muhammad participated in fights during the formation years of the Kingdom with his older brothers and cousins. In 1934, King Abdulaziz ordered his forces to attack Yemen's forward defences. Then, Faisal bin Sa'd, the son of the Saudi king's brother Saad, advanced to Baqem and the son of his other brother Mohammed, Khaled bin Muhammed, advanced to Najran and Saada. King's son Prince Faisal assumed command of the forces on the coast of Tihama and Mohammed bin Abdulaziz had advanced from Najd at the head of a reserve force to support his brother Saud.

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