There had to have been over 30 countries! You had the main axis powers Germany, Japan, and Italy. You had the main Allied powers UK, US, and Russia. There were plenty of other smaller countries involved as well
World War II started in 1939 and ended in 1945. More than 100 million people from 30 nations participated in the war, resulting in anywhere from 70 million to 85 million civilian and military casualties. World War II was the deadliest war in history. Leading up to the war, many countries tried remaining neutral.
