Faisal bin Abdulaziz Al Saud (14 April 1906 – 25 March 1975) was King of Saudi Arabia from 1964 until his assassination in 1975. Before his ascension, he served as Crown Prince of Saudi Arabia from 1953 to 1964, and he was briefly regent to his half-brother King Saud in 1964. He was prime minister from 1954 to 1960 and from 1962 to 1975. Faisal was the third son of King Abdulaziz, the founder of modern Saudi Arabia.