1 Testone - Gregory XIII Religion

Gregory XIII is best remembered for the 1582 calendar reform that replaced the Julian system with the Gregorian — a correction of roughly eleven minutes per year that had accumulated into a ten-day drift since the Council of Nicaea. The reform required a papal bull, Inter gravissimas, and the immediate suppression of ten calendar days in October of that year. Protestant nations refused adoption for over a century, treating it as a Roman provocation rather than an astronomical necessity.

Testonе coinage of this pontificate was struck at Rome under the direction of the papal mint on the Capitoline Hill.