A Seljuk Sultan offering to become Christian? Sounds a bit cray, but this actually is claimed by a contemporary participant and historian of the Fourth Crusade. Perhaps Kaykhusraw saw the crusaders intervening in Constantinople, allegedly to restore Alexios IV (though he was little more than puppet), and thought he could use them to bring himself back to power.
Robert De Clari records that Kaykhusraw went to the crusaders outside Constantinople during the Fourth Crusade and asked them to restore him to his throne:
“Lords, there is something I want to ask for you. I have a brother younger than myself who has taken from me by treason my land and seigniory of Konia (Iconium), of which I was lord and of which I am the rightful heir.”
Kaykhusraw then made his request: “If you will help me recover my land and seigniory, I will give you right plentifully of my wealth, and will have myself baptized a Christian and all those who hold of me, if I can have again my seigniory with your help.”
Robert De Clari says that “the barons answered that they would take counsel on it. So word was sent to the doge of Venice and to the marquis and all the high barons, and they assembled in a great council, and finally it was their decision that they would not do what the sultan asked of them. And when they came from their council they answered the sultan that they could not what he asked of them, because they had still to get their reward from the emperor, and it would be dangerous to leave Constantinople, as things were then, and they dared not leave it. When the sultan heard this, he was very angry and went away again.”
Imagine how different history would be if that happened!
Source:
The Conquest of Constantinople by Robert De Clari
shadowsofconstantinople.com 