The land campaign at Crécy depended in part on the earlier naval annihilation at Sluys. Chaining the French ships together surrendered maneuver and let the English attack the formation sequentially, with catastrophic losses among armored men forced into the water. The destruction of French ships and mariners explains why France later depended on hired Castilian naval power. Similar victories of annihilation at sea become possible when one fleet cannot maneuver and its opponent can defeat the formation piece by piece.
Chapter · 34:03-38:47
How Sluys made the Crécy campaign possible
Sluys eliminates the ships and mariners that might have constrained Edward's later coastal campaign toward Crécy.