Complex sentence: The university founded by Boniface VIII in 1303, had a good many students under the French popes, drawn there by the generosity of the sovereign pontiffs, who rewarded them with books or benefices.
Split into simpler sentences: The university founded by Boniface VIII in 1303 had many students under the French popes. They were drawn there by the generosity of the sovereign pontiffs who rewarded them with books or benefices.