The reign of Queen Elizabeth II, from 1952 to 2022, represents one of the longest and most defining monarchies in modern British history. Ascending the throne at age 25 following the death of her father, King George VI, Elizabeth's 70-year rule spanned profound global changes, including the decline of the British Empire, the Cold War, decolonization, and the rise of the Commonwealth. Her steadfast presence symbolized continuity amid political upheavals, with 15 British prime ministers serving under her and interactions with countless world leaders.