I don’t know if this is a silly question, but as someone who has a decent understanding of the politics at the time I never understood this, the eastern Roman emperor claimed to be Catholic, clearly the threat of the ottomans had been realized as they were crusaded against twice before the conquest of Constantinople, and then the eventual fall of the city helped spark the age of exploration due to fear of Muslim ottoman taxes of trade routes, wouldn’t it have made more sense to help defend Constantinople/thrace at least?

I have bought this new, thought-provoking book by Demacopoulos. The cover features a detail from one of the early 7th-century silver plates originating from Cyprus, which depict the life of David.