when did the us ration gas
A+E Networks. On this day in 1942, gasoline rationing began in 17 Eastern states as an attempt to help the American war effort during World War II. By the end of the year, President Franklin D. Roosevelt had ensured that mandatory gasoline rationing was in effect in all 50 states. America had been debating its entrance into World War II until the Japanese attack on Pearl Harbor on December 7, 1941.