Noteable Events:

War begins 1939
Nazi Germany loses the Battle of Britain 1940
Nazi Germany invades Denmark, Norway, Benelux, France, and the Soviet Union from 1940-1941.
The United States enter World War II after the attack on Pearl Harbor on December 7, 1941.
Germany and Japan suffer defeats at Stalingrad, El Alamein, and Midway in 1942 and 1943.
Subash Chandra Bose escapes from house-arrest and founds the INA in Singapore. The INA made of Indian POWs held by the Japanese accompanies the Japanese to the borders of India. However, Axis defeat results in the annihilation of the INA and surrender following Nethaji's death in 1945.
D-Day (June 6, 1944)
Germany surrenders May 7, 1945
Atomic bombings of Hiroshima and Nagasaki (August 6 and August 9, 1945); Japan surrenders on August 15.
World War II officially ends on September 2, 1945.
The Holocaust (the shoah)
United Nations established in 1945
In 1946, former British PM Winston S. Churchill gives his famous "Iron Curtain" speech with US President Harry S Truman present.
Beginning of the Cold War (generally thought of as somewhere from 1946-1949)
Independence for some former colonies (including India and Pakistan in 1947, Israel in 1948, and Indonesia in 1949)
1948 Arab-Israeli War
The Irish Free State becomes a republic in 1948
NATO founded in 1949
The Chinese Civil War ends in victory for the Communists in 1949. The Nationalists government retreat to Taiwan.
The Berlin blockade in 1948.
Informbiro period in Yugoslavia begins
Truman Doctrine is created.
Soviets test their first nuclear bomb in 1949 (Soviet atomic bomb project). This is seen by some as the beginning of the Cold War.