Many supposedly educated people know that the fall of Constantinople dates "only" 1453 date that we often match the late Middle Ages and the beginning of the Italian Renaissance. Admittedly, given the dramatic fall of Constantinople, Italy has recovered many of the best intellectuals of the Eastern Roman Empire.
We can not blame the Turks for pursuing a coherent geopolitical objective, however it is possible to blame the European countries have abandoned Constantinople literally, a matter of theology Orthodox Christianity was considered schismatic. Either way, the Crusades had seriously molested Constantinople, since one of them ended with the sack of the city.
On this point one can invite the interested reader to refer to profitably René Grousset and history of the Crusades in Tempus, to Jacques Heers "Fall of Constantinople and death" and of course "last but not least" and Steven Runciman his masterful new history of crusades in two volumes in the Texto collection.
On the history of Byzantium and the Eastern Roman Empire the reference remains for me the book of John Julius Norwich in the Tempus collection (14) and also a student of Steven Runciman: Donald M. Nicol "the last centuries Byzantium "in Texto collection.
It should be noted that the work of Steven Runciman contains some summary illustrations in black and white on the particular situation of Constantinople and a plan for Theodosius II ramparts which shows the existence of a complex poliorcetics which delayed the fall of the city: but the forces were too unequal ..
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