'Closed Addresses' Created By British for D-Day
In anticipation of the landings in Normandy, The British Army Postal Service developed the concept of "Closed Addresses" (e.g. No Rank Name, Unit, c/o APO England), which assisted in providing the necessary security to ensure the masking of troop movements during the build-up for D-Day and the subsequent success of Operation Overlord (D-Day landings).
An entry on the History of the British Forces Post Office website points out, "Field Post Offices were established on the beaches on D-Day. Although it was planned that mail be delivered to units on D+1, mail was delivered the following day because of confusion caused by the delay of the invasion. To ensure the safe recovery of mail for ships coming from Southampton, a Postal officer was given the job of patrolling the anchorages in an amphibious Jeep bawling through a megaphone at ship after ship “Are you carrying mail?”
"Altogether more than 12,000 airplanes, 185,000 soldiers, and 5,336 vessels, among them 4,126 landing crafts with 50,000 men on board, participated in the invasion. The naval forces consisted of American, English, French, Dutch, Greek and Polish ships, altogether 7 battleships, 2 monitors, 23 cruisers, 105 destroyers, and 1,073 smaller warships. They secured and covered 4,126 landing crafts. The Allied air forces consisted of 5,112 bombers, 2,316 torpedo planes and 5,400 fighters, " according to the Maritime Topics on Stamps website.
‘D-Day’ stands for 'departure date'.
For more on D-Day and stamps, click here.