The Future King Edward VIII on Tour
From 1919 to 1922, the Prince of Wales, the future King Edward VIII, embarked on a grand world tour.
In 1921, the Eastern Tour commenced. The HMS Renown departed Portsmouth at sunset on October 26, with the Prince on the saluting deck. The ship called at Gibraltar, Malta, Port Said, Suez and Aden before arriving at Bombay on November 17. Four months later, on March 17, the Prince left India behind as the Renown sailed for Japan.
A commemorative postmark was used during the tour of the subcontinent, featuring the legend "H.R.H The Prince of Wales' Camp P.O." at the top, with the Prince of Wales feathers in the top centre, and seven bars on each side. The date and time are at the bottom centre, with a thick bar below
Although the postmark doesn't show a location, the tour itinerary makes it possible to ascertain where the postmark was used.
The itinerary was kindly provided by Kasinath Rajasekaran on the Global Philately Facebook Page, and reproduced here in full: