Fourth Crusade

A crusade proclaimed for Jerusalem by way of Egypt, but diverted to Constantinople, where it shattered Byzantine power instead of reaching the Holy Land.

The Fourth Crusade was launched by Pope Innocent III with the stated aim of recovering Jerusalem, probably by attacking Egypt first. The army contracted with Venice for transport, but debt, Venetian strategic pressure, and Byzantine dynastic politics redirected the expedition first to Zara and then to Constantinople.

In 1204 the crusaders captured and sacked Constantinople, founding the Latin Empire. The expedition never reached the Holy Land. Its relevance to the crusader states was indirect but profound: it diverted manpower and attention away from the Levant and permanently damaged the Byzantine world that had once been the essential eastern Christian counterweight to Muslim Syria and Egypt.

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