Britain’s Queen Elizabeth II is, as of August 2022, the longest-reigning monarch in British history, and the second-longest-reigning monarch in world history, according to NPR News, having reigned over her realm since February 6, 1952. In fact, she is the only monarch most living Britons have ever known. “Inevitably a long life can pass by many milestones — my own is no exception — but I thank you all and the many others at home and overseas for your touching messages of great kindness,” she said in 2015.
Though she’s been blessed with exceptionally-long life, she can’t live forever. However, the monarchy is steeped in rules and traditions going back centuries, so when she does die, the process to identify and install the next monarch, described in exacting detail via British Heritage, will happen immediately and (hopefully) with minimal fuss. And of course, Britain’s monarchy is hereditary, which means that — barring his abdication or some other calamity — Elizabeth’s firstborn son, Charles, will become king more or less immediately.
In a weird bit of British history, Queen Elizabeth II is the longest-reigning monarch in the country’s history, while Prince Charles is simultaneously the longest-waiting heir-apparent to the throne in British history, according to Reader’s Digest.
When his mother dies, Charles becomes king more or less immediately, according to British Heritage, pending the completion of a few platitudes and formalities, including his siblings kissing his hand, a meeting with his ascension council, and so on. Then there are oaths to recite, speeches to make, etc. So in one way, Charles will become king immediately after his mother’s death (as Reader’s Digest explains it), but in another way, it doesn’t officially happen until the day following her death (as British Heritage explains it).