Wikipedia:Selected anniversaries/July 31
July 31: La Hae Hawai'i in Hawai'i, Feast day of Saint Ignatius of Loyola
- 1667 - The Treaty of Breda ended the Second Anglo-Dutch War.
- 1790 - The U.S. Patent Office issued the first patent in the United States.
- 1917 - The Battle of Passchendaele began on the Western Front in World War I.
- 1941 - Holocaust: Hermann Göring ordered SS general Reinhard Heydrich to develop a final solution to the Jewish question.
- 1971 - Apollo program: The first Lunar Rover was used during the Apollo 15 moon mission.