June 3, 1937 – The Duke of Windsor marries twice-divorced American socialite Wallis Simpson (as King Edward VIII he abdicated the British throne the previous December to avoid a constitutional crisis by marrying a divorced woman).
June 4, 1989 – The Chinese government ordered troops to open fire on unarmed protesters in Tienanmen Square, Beijing, with an estimated 3,000 killed and 1,600 arrested.
June 5, 1783 – The first sustained flight occurred as a hot air balloon was launched at Annonay, France, by brothers Joseph and Jacques Montgolfier.
June 6, 1944 – The largest seaborne invasion in history began as Allied troops undertook the D-Day invasion of Normandy during World War II. The operation began the liberation of France from Nazi control and laid the foundations of the Allied victory in Europe.