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Stephen of Blois gave up on the siege of Antioch - and the First Crusade in general - in May 1098, one day before the city fell to the Crusaders. His decision would be a classic example of the butterfly effect, with all sorts of problems for the Crusaders caused by it. Plus, when he got back, his family was so shamed by him that he was forced to go back in the stupid Crusade of the Faint-Hearted (three guesses where it got that hame) a few years later, and got himself killed for the trouble.

So, lets say that Stephen is a bit braver. Or maybe less decisive. Or Bohemond or one of the other leaders of the Crusade puts him under house (tent?) arrest and refuses to let him leave. Whatever the case, Stephen stays in Antioch, sees the city fall to the Crusaders, and then sees out the siege by the Muslims.

I'll outline the plausible best case scenario of the immediate aftermath:

- Alexios Komnenos has no reason to turn back from relieving the Crusaders and, instead, marches to relieve them. We'll assume this helps the Crusaders in their battle that broke the Siege, though that particular battle was a decisive victory for the Crusaders anyway, so not much directly changes. A few more Muslim deaths, a few fewer Christian deaths, and an earlier date for the battle, perhaps.

- With a Byzantine army present, the city will revert back to the Byzantine Empire as was the official plan anyway. It was Byzantine absence that gave the more ambitious Bohemond the opening to seize it for himself. Without that opening, much of the disputes between the Crusaders that delayed them at Antioch for half a year is dissolved, and the Crusade might continue earlier.

- With the Crusaders not lingering in Antioch, the plague that broke out there might not have happened. Bishop Adhemar, the official leader of the Crusade, might not die of disease. This helps keep the Crusaders united, keeps the Crusaders and the Byzantines on better terms. Yay. Minor Bonus: With Adhemar still alive, Peter Bartholomew might not get too big for his britches, and the Crusader faith in the Holy Lance that he found might not be diminished.

So, Byzantine-Crusader relations are better. The Byzantines have Antioch. The Crusaders aren't devastated by disease, and their leadership is more united. Thoughts?
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