1924 Great Britain, British Empire Exhibition Issue, British Lion and King George V

On April 23, 1924, Great Britain issued its first commemorative postage stamps, marking the opening day of the British Empire Exhibition at Wembley in London. The exhibition itself stood as an enormously ambitious event meant to lift the country's spirits following the First World War, showcasing goods and produce from across the Empire and ultimately drawing 27 million visitors over its two summer seasons. Prior to this issue, Great Britain had never released a commemorative stamp, arriving a full 31 years after the United States marked its own Columbian Exposition with a dedicated set in 1893.

King George V, himself an avid stamp collector, initially expressed reservations about commemorative stamps, reportedly dismissing them as funny and un-English, though he ultimately gave his consent provided the project was handled properly. The Post Office invited submissions from several artists for a design symbolic of the British Empire, ultimately selecting artist Harold Nelson's depiction of a British lion, which would come to be known as the Wembley Lion. Nelson paired the lion with a portrait of the King originally created for the Seahorses high value stamps first issued in 1913, choosing to print the same design in two different colors for the penny and three halfpence denominations rather than adopting separate artwork for each value.

The two stamps proved so popular with the public that officials reissued the same design the following year when the exhibition reopened for its second summer season, updating only the printed date from 1924 to 1925. Waterlow and Sons printed more than fifteen million of the stamps to meet demand surrounding the exhibition. Known among collectors simply as the Wembleys, these two stamps opened a new chapter in British philately, establishing a tradition of commemorative issues that continues to this day.