LONDON (NEWSnet/AP) — Queen Elizabeth II, Britain’s longest-reigning monarch, died Thursday. She was 96.

Buckingham Palace announced she died at Balmoral Castle, her summer residence in Scotland, where members of the royal family had rushed to her side after her health took a turn for the worse.

Her 73-year-old son Charles automatically became king and will be known as King Charles III, his office announced. Charles' second wife, Camilla, will be known as the Queen Consort.

The impact of her loss will be huge and unpredictable, both for the nation and for the monarchy, an institution she helped stabilize and modernize across decades of enormous social change and family scandals.

Charles called the death of his mother “a moment of the greatest sadness for me and all members of my family,” adding: “I know her loss will be deeply felt throughout the country, the Realms and the Commonwealth, and by countless people around the world.”

British Prime Minister Liz Truss, appointed by the queen just 48 hours earlier, pronounced the country “devastated” and called Elizabeth “the rock on which modern Britain was built.”

President Joe Biden called her a “stateswoman of unmatched dignity and constancy who deepened the bedrock alliance between the United Kingdom and the United States.”

Since Feb. 6, 1952, Elizabeth reigned over a Britain that rebuilt from a ruinous war and lost its empire; joined the European Union and then left it; and made the painful transition into the 21st century. She endured through 15 prime ministers, from Winston Churchill to Truss — a fixed point and a reassuring presence even for those who ignored or loathed the monarchy.

She became less visible in her final years as age and frailty curtailed public appearances, and she used a cane after the April 2021 death of Philip, her husband of 73 years. She was hospitalized for a night for tests later that year.

But she remained firmly in control of the monarchy and at the center of national life as Britain celebrated her Platinum Jubilee in June. That same month, she became the second-longest-reigning monarch in history, behind 17th century French King Louis XIV, who took the throne at age 4.

In 1947, almost five years before she ascended the throne, the 21-year-old Elizabeth promised the people of Britain and the Commonwealth that “my whole life, whether it be long or short, shall be devoted to your service.”

It was a promise she kept across more than seven decades.

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