Fahd suffered a severe stroke in 19995, which weakened him both physically and mentally, and he turned over much of the day-to-day running of the kingdom to Crown Prince Abdullah.
Fahd, the son of Saudi Arabia's founder, King Abdul Aziz al-Saud, entered public life when he was in his early twenties, serving under his brother, Faisal, who was foreign minister at the time.
He then served as education minister and interior minister and when Khalid became king in 1975, Fahd was named as crown prince.
Fahd engaged his country more than his predecessors had in regional and international affairs. He played a big role trying to end Lebanon's 15-year-long civil war, hosting peace talks between the warring factions in Taif in 1989.
In 1981, Fahd drew up a peace plan for the Middle East that was adopted at an Arab League summit the following year.
He was also an ardent supporter of the mujahedin in the 1980s in their fight against the former Soviet Union's occupation in Afghanistan.
King Fahd has sought to highlight his country as the leader of the Islamic world and in 1986, he adopted the title of Custodian of the Two Holy Places -- Mecca and Medina.
He will be succeeded by his brother, Abdullah.