In 1991, ten major events or developments of 1941 are depicted on the first of five scheduled sheetlets, one to be issued each year, to commemorate the 50th anniversary of World War II. These sheetlets are a mini-course in the events that took place throughout the war years. In the center of this first sheetlet is a map of the world, showing the countries at war in 1941 and pinpointing locations of major events and conflicts that year. Each of the 10 attached stamps deals with a specific subject - such as the Burma Road, a supply route for Chinese war materials, and the Japanese bombing of Pearl Harbor. Japan worried about a possible anti-Japanese backlash during the observance of the 50th anniversary of that fateful event. Military historians from the U.S. Department of State and all branches of the Armed Services, along with the Citizen's Stamp Advisory Committee, helped decide which subjects would be featured on these and the 40 other stamps issued in 1991-95.