This is a list of selected July 31 anniversaries that appear in the "On this day" section of the Main Page. To suggest a new item, in most cases, you can be bold and edit this page. Please read the selected anniversaries guidelines before making your edit. However, if your addition might be controversial or on a day that is or will soon be on the Main Page, please post your suggestion on the talk page instead.
Please note that the events listed on the Main Page are chosen based more on relative article quality and to maintain a mix of topics, not based solely on how important or significant their subjects are. Only four to five events are posted at a time and thus not everything that is "most important and significant" can be listed. In addition, an event is generally not posted this year if it is also the subject of the scheduled featured article or picture of the day.
To report an error when this appears on the Main Page, see Main Page errors. Please remember that this list defers to the supporting articles, so it is best to achieve consensus and make any necessary changes there first.
July 31: Ka Hae Hawai‘i Day in Hawai'i; Feast day of Saint Ignatius of Loyola
- 1667 – The Second Anglo-Dutch War between England and the United Provinces ended with the signing of the Treaty of Breda in the Dutch city of Breda.
- 1703 – English writer Daniel Defoe was placed in a pillory for seditious libel after publishing a pamphlet politically satirising the High Church Tories.
- 1777 – The Second Continental Congress passed a resolution allowing French nobleman Marquis de Lafayette to enter the American revolutionary forces as a Major General.
- 1971 – Apollo program: The first Lunar Rover (pictured) was used during the Apollo 15 mission to the moon.
- 2006 – Following intestinal surgery, Fidel Castro provisionally transferred the duties of the Cuban presidency to his brother Raúl.