New Delhi, April 23 -- Queen Elizabeth II lives on at the Cool Britannia gift shop across the road from Buckingham Palace.

Four years after the queen's death, the shop is doing a brisk business in mugs, tea towels and key rings bearing the likeness of Britain's longest-reigning monarch as the nation marks the centenary of her birth on Tuesday. Items featuring her son King Charles III? Well, not so much.

"We still sell more than the king any day,'' said Ismail Ibrahim, the store's manager.

The late queen's memory looms over the monarchy after a 70-year reign that saw her evolve from the glamorous young sovereign who cheered Britain during the gloomy post-war years to the beloved national grandmother who rallied the country during the CO...