The fourth crusade: a plot?

Was there a "plot" to divert the Fourth Crusade to Constantinople, and if so who was responsible? "We will never know, and science has truly something better to do than to discuss indefinitely an insoluble problem" -P. Mitrofanov This famous comment on the fourth crusade and the question of a "plot" was made well over a century ago, and very little new evidence has emerged since. So why return to this topic? Most modern historians …

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