if the papacy sinned, it was not without partners. In the real world of shifting political balances and every ruler’s constant need of money, popes and kings needed each other and made the necessary adjustments. They dealt in territories and sovereignties, men-at-arms, alliances, and loans. A regular method was the levy for a crusade, which allowed ecclesiastical income within each country to be taxed by its king, who soon came to regard it as a right.
