1666
year
1666 (MDCLXVI) was a common year starting on Friday of the Gregorian calendar and a common year starting on Monday of the Julian calendar, the 1666th year of the Common Era (CE) and Anno Domini (AD) designations, the 666th year of the 2nd millennium, the 66th year of the 17th century, and the 7th year of the 1660s decade. As of the start of 1666, the Gregorian calendar was 10 days ahead of the Julian calendar, which remained in localized use until 1923. This is the first year to be designated as an Annus mirabilis, in John Dryden's 1667 poem so titled, celebrating England's failure to be beaten either by the Dutch or by fire.
Events
January–March
January 17 – The Chair of Saint Peter (Cathedra Petri, designed by Bernini) is set above the altar in St. Peter's Basilica in Rome.
January 27 – Mughal conquest of Chittagong: Mughal forces of Emperor Aurangzeb, in alliance with the Portuguese, under Shaista Khan and his son Buzurg Umed Khan, expel the Maghs from the Bengal port city of Chittagong, renaming the city as Islamabad.
February 1 – The joint English and Scottish royal court returns to London as the Great Plague of London subsides.
March 11 – The tower of St. Peter's Church, Riga, collapses, burying eight people in the rubble.
March – The Tavernier Blue, precursor to the Hope Diamond, is first recorded, when French gem merchant Jean-Baptiste Tavernier purchases it from the Kollur Mine in the Mughal Empire in uncut form.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Jul 25, 2026. The linked authority identifier is Q7585. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1666, 1923 and 1667.
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This entry incorporates text from “1666” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.