Montreuil was a thriving port before the river silted up in the 1300s (the sea is now about 25 km away).
Many people lost money as a result of the river silting up in Montreuil.
mnli hypothesis: Many people lost money as a result of the river silting up in Montreuil. premise: Montreuil was a thriving port before the river silted up in the 1300s (the sea is now about 25 km away).