How much longer would the Byzantine Empire have lasted if it had succeeded in repelling the Ottomans in 1453?

Nothing, a couple of years at most. The Ottomans had been attacking Constantinople for decades, not to mention they were completely surrounded. The ERE was virtually non-existent by 1400

The problem wasn't the Ottomans, it was the crusade that pretty much fucked Byzantium and prepared its grave.

Without that, they may have lasted a bit longer before dying from the inside, but with the crusade they wouldn't have made it anyway.

>it was the crusade that pretty much fucked Byzantium and prepared its grave
If you're an empire, but a fucking city state owns your economy and with a few mercs can take you down, you're already done. The 4th crusade wouldn't have happened if the rest of the world wasn't already aware of the absolute weakness of the ERE.

You can blame the Angeloi usurpers for that. Shame Manuel died to early

byzantium had a lot of ups and down.after heraclius and the loss of syria and egypt ere was in a bad shape.still it hold carthagen and ravenna-rome till early 8th century.macedonian dynasty and Basil II made an empire again with all of greece ,south balkans some south italian cities and all of anatolia.but after 1071 ere was in deep shit.still another resurgence with komnenoi who almost secured half of anatolia.1204 was the last hit.after that it was a dying small empire.still impressive that seljuks and franks and ottomans needed collectively almost 350 years to take it down completely.Constantinople was a hard beast to capture

To be honest it was already as Impressive for it to survive as it is, literally no one else survived as much as they did with only their Western counterpart even coming close to compare

What did Constantinople look like in its last days? Considering the damage the 4th crusade did. Probably not too good.

Not much longer. The Sack of 1204 is what did the Byzantines in. As long as their wealthy capital remained intact, they would have had a chance to recover.

However. after the plunder and the loss of most of their treasury and precious works, as well as their technical manuals and the disruption of their trade routes and merchant contacts and the scattering of the nobility and bureaucracy and the slaughtering of a significant percentage of the city's population, plus mismanagement by the Latins and the implementation of feudalism on a state that had never adopted it, it was a miracle they even managed to take back Constantinople in 1261.

2 years, tops.

>tfw the Roman state existed in some way from the 8th century BC until the 15th century AD
I TRIED SO HARD

>their technical manuals

>the implementation of feudalism on a state that had never adopted it
Let's be honest here, the pronoia system was basically just that.

>Eastern
>Roman
>Empire

Yes, technical matters. Manuals on civil engineering, on weapons manufacturing, on various state secrets (silk-making, etc.). One example is how the recipe for making Greek Fire was lost during the sack of the city.

No, it wasn't. The pronoia system was very different from feudalism - for one, the pronoia system carried no military association once service had been completed. Pronoiars could not themselves become lords and have peasants on their lands who were tied to it, since the pronoia land grants were generally small allotments for an individual and his family, if relevant. Not all pronoiars were even farmers, and some were merchants who used the land grants to build vacation houses or to grow some crops to sell for commercial enterprise, perhaps even hiring wage laborers.

it still exists though

What about the dynatoi then? They flourished during the Komnenian era

>Battle of Manzikert
>4th Crusade
>Great Schism (breaking ties with the west, though they'd done that before too)

The question is. How did escape the Mongols?

Just having the city of Constantinople alone wouldn't have saved the Byzantines, the 4th Crusade and the sack of the city merely hastened their decline after all. And no people, no empire, is going to recover when reduced to a small strip of land and a single city while economically choking to death and surrounded on all sides by hostiles in both Europe and Asia.

Same way the Sassanids did the Huns.

mongols never made it that far and besides they had plenty of experience fighting steppemonkeys

the fall of Constantinople was the Ottoman's third try, actually. with 2 previous assaults beaten back

en.wikipedia.org/wiki/Siege_of_Constantinople_(1411)

en.wikipedia.org/wiki/Siege_of_Constantinople_(1422)

It would maybe take a decade or 2 to get the resources for another great siege, but for the non-existent Byzantines to throw back the Ottomans twice before falling is pretty amazing imho.

What about the dynatoi? Even the dynatoi were markedly different from the feudal lords of the West - many dynatoi were senior bureaucrats/politicians rather than hereditary princes or feudal lords.

Bureaucrats - something that did not even exist in the West from the fall of the Roman Empire until the 17th century.

Two weeks