On July 9, 1799, Washington finished making his last will; the longest provision concerned slavery. All his slaves were to be freed after the death of his wife Martha. Washington said he did not free them immediately because his slaves intermarried with his wife's dower slaves. He forbade their sale or transportation out of Virginia. His will provided that old and young freed people be taken care of indefinitely; younger ones were to be taught to read and write and placed in suitable occupations. Washington freed more than 160 slaves, including 25 he had acquired from his wife's brother in payment of a debt freed by graduation. He was among the few large slave-holding Virginians during the Revolutionary Era who emancipated their slaves.

On 9 July the Allies invaded Sicily in Operation Husky. German signals intercepted by GC&CS showed that even four hours after the invasion of Sicily began, twenty-one aircraft left Sicily to reinforce Sardinia. For a considerable time after the initial invasion, Hitler was still convinced that an attack on the Balkans was imminent, and in late July he sent General Erwin Rommel to Salonika to prepare the defence of the region. By the time the German high command realised the mistake, it was too late to make a difference.

The royal couple went on to officially confirm their engagement on July 9th, 1947, and hosted a photocall at Buckingham Palace, which allowed the future monarch to show off her new diamond ring.

The Russell–Einstein Manifesto was issued in London on July 9, 1955, by Bertrand Russell in the midst of the Cold War. It highlighted the dangers posed by nuclear weapons and called for world leaders to seek peaceful resolutions to international conflict.

On 9 July, she awoke in her bedroom at Buckingham Palace to find an intruder, Michael Fagan, in the room with her. In a serious lapse of security, assistance only arrived after two calls to the Palace police switchboard.