Queen Elizabeth II, the longest-reigning British monarch whose rule spanned seven decades, died on Thursday at the age of 96, Buckingham Palace has announced.

Elizabeth ascended to the throne in 1952, on the death of her father, King George VI. She oversaw the last throes of the British empire, weathered global upheaval and domestic scandal, and dramatically modernized the monarchy. She died at Balmoral Castle in ScotlandĀ after doctors said they had become concerned about her health. Elizabeth ruled over theĀ United KingdomĀ and 14 other Commonwealth realms, and became one of the most recognizable women ever to have lived. Her son, Charles, immediately became King upon her death.

Charles immediately became King upon the death of his mother, Queen Elizabeth II. As heir apparent since the age of three, he has been the longest serving heir to the throne in British history. Upon becoming the sovereign, Charles has the option to take any name he chooses for his reign as King. For example,Ā King George VIā€™s real name was actually Albert. Two previous monarchs have been called Charles.

Charles had already been taking on some of the Queen’s engagements this year as her health had become enough of a concern for her to cancel some of her commitments, including theĀ State Opening of Parliament. Both Charles and Prince William had been prioritizing the Queen’s diary over theirs. Both of them had been activated as Counsellors of State, where the Queen delegates her sovereign power for specific purposes, and they were obligated to be even more available for those duties.