The New Revelation of Henri, God's Second Son, was the form of Christianity that arose after the Great Black Deaths killed 80% of Europe's population. The devastation wrought by the plague left Europe open to Muslim conquest, and a charismatic leader arose named Henri who claimed to be God's second Son and the deliverer of the Final Testament.
The Pope (then based in Avignon) and the King of France declared Henri to be a heretic, and ordered him executed on the wheel. However, the death of both the King of France and the Pope the very next day as a result of a church collapsing convinced most Christians that Henri was indeed correct. He was soon worshiped as a martyr after his death, and Christians were more likely to sketch the sign of the wheel than the sign of the cross--the symbol of God's First Son. In addition, churches were subsequently built with two steeples, a shorter one in front of a taller one with a cross on the shorter and a wheel on the taller.
One result of Henri's status as a "Son of God" was a deepening of the division between Christianity and Islam. While rejecting Jesus' divinity, Islam recognized him as a true Prophet of God. However, since it was a fundamental tenet of Islam that Muhammad was "The Seal of the Prophets", and there would be no prophets after him, Muslims regarded Henri as a tool of Satan.
For its part, the Church gave to the part added to the Bible and describing Henri's life and death the name "The Final Testament" - a name implying that, while the Church hierarchy did have to accept Henri's divinity, they were not ready for a third Son of God to suddenly appear somewhere.