Editing 1691 (section)

=== Date unknown ===
* [[HMNB Devonport]], currently one of three operating bases in the United Kingdom for the Royal Navy and the largest naval base in Western Europe, opens.
* [[Michel Rolle]] invents [[Rolle's theorem]], which states that any real-valued [[differentiable function]] that attains equal values at two distinct points must have at least one [[stationary point]] somewhere between them.
* The [[Khalkha]] submit to the [[Manchu people|Manchu]] invaders, bringing most of modern-day [[Mongolia]] under the rule of the [[Qing Dynasty]].
* [[Nimavar school]] in [[Isfahan]], [[Iran]] is built and opens in this era of [[Suleiman I of Persia|Suleiman I]].
* The textile factory ''[[Barnängens manufaktur]]'' is founded in [[Stockholm]], [[Sweden]].
* The [[Society for the Reformation of Manners]] is founded in the [[London Borough of Tower Hamlets]] with the aim of suppressing [[profanity]], [[immorality]], and other lewd activities in general, and of [[brothel]]s and [[prostitution]] in particular.
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