In October 1582, Pope Gregory XIII deleted ten days from existence—October 4th jumped to October 15th. It wasn’t just a calendar fix. It was a claim of power: who gets to decide when “now” is?Protestant England refused the Gregorian calendar for 170 years, running days behind Catholic Europe as an act of jurisdictional resistance. The fallout wasn’t theoretical: merchants lost cargo, insurance dates became invalid across borders, ships missed tides, contracts collapsed, and even births and marriages became legally incompatible between nations.Eventually, the cost of “time sovereignty” became too high. Britain switched in 1752, Russia in 1918, Greece in 1923—and the last visible dispute still lingers in how some churches calculate Easter.Today, every timestamp, treaty, and dated document runs on a standard born from that 1582 decree… so completely normalized that the authority behind it became invisible.We obey a centuries-old jurisdiction every time we write the date.