The Deobandi JUI Movement
The Jamiat Ulema-i-Islam party originated from pre-partitioned India towards the final stages of the British Raj. It was originally opposed to the idea of the creation of Pakistan and drew its support from the Deobandi religious seminaries. When Pakistan eventuated, some of JUI became pro-Pakistani and organised themselves there as a religious political front. There are currently three main factions of the JUI and it has spawned a number of militant breakaway movements such as the Sipahi Sahaba-e-Pakistan and Harakat ul-Mujahideen.
Jamiat Ulema-i-Islam (Sami faction)
The leader of this movement is Maulana Sami ul-Haq who is the founder of the Daar ul-Uloom Haqqania in Akhora Khattak of Pakistan's NWFP province. An ethnic Pashtun, Sami was instrumental in the nurturing and creation of the Taliban movement in Afghanistan. He was placed under house arrest for fear by the Pakistani government of formenting anti-US protests during the anti-terror bombing raids against the Taliban.
Jamiat Ulema-i-Islam (Fazlur faction)
Maulana Fazlur-Rahman is head of his own faction of JUI and is a pro-Taliban supporter. He contested the D.I Khan constituency in past elections. Recently he was placed under house arrest by te Pakistani military during the initial stages of US bombardment of Taliban positions in Afghansitan.
Jamiat Ulema-i-Islam (Qadri faction)
I have no idea what Maulana Ajmal Qadri does.