Buckingham Palace said the queen, who was 96, died peacefully at Balmoral Castle, her estate in the Scottish Highlands. Her son became Britain’s new monarch, King Charles III.

The death of Queen Elizabeth II, which Buckingham Palace announced on Thursday, is a watershed moment for Britain, at once incomparable and incalculable.

It marks both the loss of a revered monarch — the only one most Britons have ever known — and the end of a figure who served as a living link to the glories of World War II Britain, presided over its fitful adjustment to a post-colonial, post-imperial era and saw it through its bitter divorce from the European Union.

The official Twitter account for Prince William, King Charles III’s eldest son, has been updated. William is now the heir to the throne. The Twitter account for William and his wife, Catherine, has been updated to reflect an apparent change in the couple’s titles, and now refers to them as the Duke and Duchess of Cornwall and Cambridge. The pair were previously known as the Duke and Duchess of Cambridge, but now appear to have taken the additional title that previously belonged to Charles and his wife, Camilla.