Hussain bin. Mansoor al hallaj, a controversial Sufi of Islam. He is the only person in the history of Sufism who claimed 'I am haqq' which is translated as I am the truth. In Islam, God is one and human being can't replace Him. He is alone, the creator of the universe and he holds of everything between heavens and earth. If somebody claims to be God, he will remain a human being, but in Islam there is a code to punish him. Hussain bin. Mansoor was punished by his master Shaykh Junaid al Bagdad by ordering 'hang him'.
He was hanged and there are numerous stories attached to him. He remained controversial throughout his life. Ali. bin Uthman al hajveri discussed him in kashaf al Mahjub.