Operation Magic Carpet, 1945-1946
In 1943, the US Army realized it had a problem. World War II would eventually end, and they would then need to get everybody home. With some 16,000,000 people in one uniform or another, and most of them with at least one Ocean separating them from the US, it became obvious that they would need to set up a way to get them home. Fortunately, the US was hard at work building as many ships and aircraft as it could, so most should be available to make transport runs when peace broke out, even if they weren't designed for it. Planning for the mass movement of decommissioned service personnel was given to the War Shipping Administration, and by 1945, they had a solid plan in place. After the surrender of Germany, the Army and Merchant Marine were in charge of the return of personnel, but after Japan surrendered, the Navy also joined in. Troop transports were ideal for use, since they were already set up for transporting people, but large warships, and particularly aircraft carriers, had the space to accommodate hundreds, or even thousands, of returning people. USS Lake Champlain was committed straight to Operation Magic Carpet when she commissioned in October, 1945, and was fitted with bunks to accommodate 3,300 passengers.
Magic Carpet went both ways, too. Ships heading back to the former front would also take prisoners of war from their internment camps back to their native countries. Approximately 450,000 Germans and 53,000 Italians were returned from the US to Europe by ships heading back for another load of Americans. The European portion of Magic Carpet was wrapped up in February, 1946, with the operation officially concluded in April, but the Pacific phase continued until September. By the end, less than 1,600,000 people remained in uniform.
It should also be noted, that the British Commonwealth faced the same problem, and successfully executed a similar operation to bring their troops home, though it lacked the catchy nickname. The Americans had also conducted a similar operation after the end of World War I, though it was much smaller in scale.