Looking at the discussions on the Byzantines on here, I'd gotten the idea of having a surviving Byzantine Empire, with a POD in 1204. Recently, Ioannes came up with
another 1204 idea, somewhat similar to what I had been thinking about. I thought about posting in Ioannes thread, but it turned into a TL and I didn't want to distract from the discussion, so I thought I'd start another thread.
Basically, my idea is:
For whatever reason, the 4th Crusade goes to the Holy Land like it was supposed to. It probably doesn't have any more effect than the other crusades to the Holy Land did.
The Byzantines continue on their merry way until 1258, when Hulegu Khan sacks Baghdad. The current Byzantine Emperor (probably an Angeloi, they seem vain/stupid enough for this) decides to invite Hulegu into Anatolia as an ally against the Seljuks. Hulegu obligingly crushes them and plunders all their territory, but then decides that, since he's proven himself to be so powerful, the Byzantines should pay him tribute. The Byzantines, naturally, are not so keen on this, and after a nice bit of diplomatic wrangling, Hulegu attacks the Byzantines.
Our Angeloi raises and army to fight the Mongols in Anatolia...and promptly looses all his forces to the Mongol cavalry archers. The Mongols pillage Bursa, Nicaea, and Nicomendia, then decide to try for Constantinople itself. The scour the Anatolian coastline, looking for anything that floats, and eventually gather together a nice mass of requisitioned fishing boats and smaller merchant ships to ferry their army across the Bosphorus. Byzantium's decayed navy is too weak to stop them, but the Byzantines send emmisaries to the Italians, who are shocked at the degree of destruction visited on Byzantium's Asia Minor possessions and don't wish the same to happen to the rest of the Balkans (because it might affect their trade, and the Mongols might go after them eventually)
Genoa, Pisa, and Venice all send naval help to the Byzantines, and the Mongols, who have no real naval experience (or real navy, for that matter), are unable to keep supplies from getting to Constantinople, or regularly resupply their own forces across the Bosphorus. Unable to storm Constantinople or starve it out, the Mongol siege goes on and on, until finally they get tired of it and promise to go away in exchange for a nice tribute, which the Italians and Byzantines scrape together. The Mongols leave, and, having been unable to pillage Constantinople, take their frustrations out on the already-subdued Seljuk lands, which between two Mongol smash-and-grab expeditions are as badly ravaged as Central Asia and Iran were by Genghis Khan. (I thought of having the Byzantines get the Mongols to attack Bulgaria before they leave the Balkans, but this might make things a little too convenient...)
The Byzantine-Mongol war comes as a massive blow to Byzantine pride, revealing just how badly their army and navy have decayed. Our Angeloi either dies during the war or gets overthrown shortly after it, replaced by a military strongman (I'm thinking that possibly Michael Paleiologos could fill this role, or alternately-and possibly better-a general with no connections to the previous royal family, who made a name for himself in the war). At any rate, our new emperor immediately sets about rebuilding the army, incorporating cavalry archers (based on Byzantine experience with Mongol ones) as well as traditional European melee cavalry and heavy infantry, influenced by the Italian and Iberian models the Byzantines would have come into contact with. Additionally, Emperor Strongman begins rebuilding the Byzantine navy into a viable fighting force, and makes some reforms to administration and tax collection to help pay for everything.
With their newly rebuilt army and navy, the Byzantines begin pushing into formerly Seljuk Anatolia, which has been damaged even worse than OTL and broken up into ten or twelve warring states. By 1300, after a series of campaigns, the Byzantines have retaken the western third of Anatolia, which is filled with extensive Greek colonies and fiefs (given on uncultivated land-the lord promises to bring said land under cultivation and provide cavalry for the Byzantine army, helping the army further develop its strength in that area). The Byzantines also have successes against the Bulgarians, gradually conquering them over the course of the 14th century, and continue to retake Anatolia.
I haven't quite decided what would happen after this, and I've sworn off TL writing for the time being (I have school, and I'm kind of bad at developing my TLs beyond the initial idea). Also, I'm afraid its too similar to Ioannes' TL. Still, I'm curious as to what you guys think of it, and where this could go.