If you look at a changing map of the Eastern Roman Empire over time, like the Western Roman Empire, it "collapsed" well before it fell. Many educated elites fr

If you look at a changing map of the Eastern Roman Empire over time, like the Western Roman Empire, it "collapsed" well before it fell. Many educated elites from Rome moved to Constantinople a century before Rome fell. ...and similarly, the most educated elites left Constantinople for northern Italy (and Russia!) before the Ottomans smashed down the walls over the preceding century.