Fourth Crusade, the routes travelled

What you are looking at

Two lines. Venice to Zara in the autumn of 1202, and Zara through Corfu to Constantinople in the spring of 1203.

How to read this layer

Both lines are dashed, which in this project always means Terra Chartarum drew them. No source in the corpus gives a track: Villehardouin and Clari describe a sequence of ports and events, not a course, and a solid line here would claim a precision the chronicles do not have.

What the lines are good for is shape. They show a fleet working down one coast and across to another, which is the thing the Sea proof is about, and they are drawn so that nobody measures them.

What is deliberately not here

Three of the six states of this campaign have no geometry, and their absence is part of the argument:

• The intended destination. Egypt, in the 1201 agreement. It was a clause in a contract, and an arrow to a coast the fleet never approached would make an intention look like a movement.
• The partition claim. The Partitio Romaniae divided an empire among people who held very little of it. Its boundaries are disputed in the scholarship, and drawing them would publish a claim as a map.
• Durable control. What was actually held after 1204 was far less than the Partitio assigned and was contested throughout. The Venetian possessions layer already models phased extents with their own evidence, and this pilot points at it rather than re-authoring it.

Historical scope

1202 to 1203 for the travelled routes. The wider campaign runs to 1204 and its consequences to 1261; those are in the event and state records.

Sources and evidence

Villehardouin and Clari for the movement, the 1201 treaty for what was contracted, Choniates for the city’s own account of what happened when the fleet arrived. Every locator reads pending and no witness is cleared.

Reconstruction and uncertainty

Confidence is low on both lines, and that is about the geometry rather than about the events: that the fleet went from Venice to Zara is not in doubt, and the path it took between them is not recorded.

Editorial decisions

This layer reuses rather than rebuilds. Where the campaign crosses waters the Venetian Maritime Network already publishes, the state records point at those layers by name.

Data fields

See the Crusades data fields.

Data and downloads

CC BY 4.0 for the compiled records. In review; not citable as established evidence.