For the causes of the “price revolution” in the 16th and 17th centuries, the evidence is more secure. The Spanish monetary inflation from the exploitation of the gold and silver mines of the new world. For example:
For the earlier period, the evidence is not so clear. David Hacket Fisher argues that the previous price inflation coincided with the beginning of the hundred year’s war and the black death. If that’s the case, then it was caused by a reduction in production and not an increase in the money stock. See his book, The Great Wave: Price Revolutions and the Rhythm of History.
The increases in the money stock prior to the price revolution of the 16th century came from silver mines in central Europe. Jim Bolton in his book, Money in the Medieval English Economy, 973-1489, estimates that the silver money stock in England increased 27 to 40 fold from 1086 to 1300.
Bolton relies on Martin Allen’s book, Mints and Money in Medieval England.