Hassan al-Turabi (1932-) is a Sudanese politician and Islamic scholar. Within Sudanese politics, his role has ranged from a "philosopher-king" of no official status but immense influence, to Speaker of the parliament, to political prisoner. He described his approach as an "Islamic experiment", with hard proselytizing, sometimes by force, but then with a relatively moderate approach to enforcing Islamic law. He was Osama bin Laden's patron while bin Laden was based in Sudan.
He was born to a Sufi leader, and took graduate degrees in law in London and Paris; he was the first Sudanese to earn a doctorate from the Sorbonne. He joined the Muslim Brotherhood in Sudan, and became secretary-general, between 1964 and 1969, of the Islamic Charter Front, the Sudanese branch of the Brotherhood, which called for an Islamic constitution. 
He was imprisoned after a coup that brought Jaafar Nimeiri to power in 1969, he was jailed for six years, then went to exile in Libya. Nimeiri, in a 1979 move to bring Islamists into the government, appointed him attorney general. This began a back-and-forth between Turabi's Islamic approach and a more pragmatic approach of military leaders, beginning with Nimeiri and continuing to the present Omar al-Bashir.
National Islamic Front
Before the 1985 coup, led by [ al-Bashir]] that overthrew Nimeiri, Turabi was imprisoned. When freed, he restructured the Islamic Charter Front into the National Islamic Front (NIF).
Osama bin Laden
In an interview, Turabi said bin Laden only visited his home once, and their relationship was cool; he described bin Laden as an investor rather than part of public life. While Turabi said he never invited him for dinner, Turabi's wife spoke of hosting the bin Ladens for a small dinner, but "Sheikh Osama was not such an important person in the Sudan." The U.S. 9/11 Commission, however, said "By the fall of 1989, Bin Ladin had sufficient stature among Islamic extremists that a Sudanese political leader, Hassan al Turabi, urged him to transplant his whole organization to Sudan... Bin Ladin agreed to help Turabi in an ongoing war against African Christian separatists in southern Sudan and also to do some road building. Turabi in return would let Bin Ladin use Sudan as a base for worldwide business operations and for preparations for jihad." 
One of the factors in the most recent Sudanese civil war was the objection of South Sudan to the imposition of Islamic law and Arabic language on a population of mixed religion and ethnicity. Al-Turabi was especially associated with this position.
While the NIF achieved 3rd place in the 1986 elections, and he became minister of justice, attorney general, minister of foreign affairs, and eventually deputy prime minister, he resigned all posts in 1989. The NIF refused to endorse a power-sharing agreement with the major southern organization, the Sudanese People's Liberation Movement. He was briefly imprisoned, but returned to the Northern government.
He has been supportive of one of the Darfur resistance groups, the Justice and Equality Movement (JEM).
Threats against Khartoum
In May 2008, he was arrested after JEM members attacked Khartoum, although he was later released.
- Milton Viorst (2001), In the Shadow of the Prophet, Westview, ISBN 0813339022, p. 109
- "Profile: Sudan's Islamist leader", BBC News, 15 January 2009
- Peter L. Bergen (2006), The Osama bin Laden I Know: An Oral History of al Qaeda's Leader, Free Press, ISBN 0743278917, pp. 122-123
- National Commission on Terrorist Attacks Upon the United States (also known as the 9-11 Commission) (2004), The 9/11 Commission Report, p. 57
- Stephen F. Hayes (November 24, 2003), "Case Closed: The U.S. government's secret memo detailing cooperation between Saddam Hussein and Osama bin Laden.", Weekly Standard (U.K.) 9 (11)
- Andrew McGregor (May 15, 2008), "Darfur’s JEM Rebels Bring the War to Khartoum", Terrorism Monitor, Jamestown Institute