Wikipedia:Selected anniversaries/January 31
This is a list of selected January 31 anniversaries that appears on 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 soon will 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 5–6 events are posted at a time and thus not everything that is "most important and significant" can be listed. In addition, an event is not generally posted this year if it is also the subject of the scheduled January 31, 2020 featured article or the January 31, 2020 featured picture.
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.
- 1578 – Eighty Years' War: Spain won a crushing victory in the Battle of Gembloux, leading to a break up of the United Seventeen Provinces into the Union of Arras (Catholic South) and Union of Utrecht (Protestant North).
- 1747 – The London Lock Hospital, the first clinic specialising in the treatment of venereal diseases, opened.
- 1862 – American astronomer Alvan Graham Clark first observed the faint white dwarf companion of Sirius, the brightest star in the night sky.
- 1961 – Aboard NASA's Mercury-Redstone 2, Ham the Chimp (pictured) became the first hominid launched into outer space.
- 2007 – Suspects were arrested in Birmingham, England, accused of plotting to kidnap, and eventually behead, a Muslim British soldier serving in Iraq.