From where do the soil in the indus valley receive its rich silt

Mesopotamia. But other river civilizations had silt also.

In the 1300s, the Church encountered a series of problems. These problems led to a decline in the Church's power. European kings had begun to reject papal claims of supremacy by the end of the 1200s. The struggle between Pope Boniface VIII and King Philip IV of France had serious consequences for the papacy.