The photograph shows the Empire Day Parade passing the Town Hall and proceeding along Wellington Road. It was not until after Queen Victoria’s death in 1901 that Empire Day was first celebrated. The first Empire Day took place on May 24th 1902, the Queen’s Birthday. It was an occasion for demonstrating pride in the British Empire that spanned a quarter of the globe, and for generally having a good time.
In 1958 it was renamed British Commonwealth Day and in 1966 it became simply, Commonwealth Day. For further information follow the link: