1684
Edmond Halley Visits Newton
The young English astronomer Edmond Halley traveled to Cambridge to ask Isaac Newton what path a planet would follow under an inverse-square force. An ellipse, Newton replied instantly; he had calculated it years earlier but lost the paper. Halley persuaded him to write it up, and Principia Mathematica was born.
Kangxi Emperor Annexes Taiwan
Qing naval forces under Admiral Shi Lang crossed the Taiwan Strait and defeated the remnants of the Zheng family fleet, the last Ming loyalist holdout. Taiwan was formally incorporated into the Qing Empire as part of Fujian Province. The island that had been a pirate kingdom and a Dutch colony became Chinese territory for the first time.
Versailles Receives the Siamese Embassy
A delegation from King Narai of Ayutthaya arrived at Versailles bearing gifts of gold, silk, and lacquerware for Louis XIV. The Sun King, enchanted by the exoticism, sent Jesuits and soldiers to Siam in return. The brief Franco-Siamese alliance collapsed within five years, but it produced some of the century's most vivid diplomatic theater.
Holy League Formed
Under Pope Innocent XI's mediation, Austria, Poland, Venice, and later Russia joined in a Holy League to push the Ottomans back from Europe. The resulting war, lasting sixteen years, would drive the Turks out of Hungary and into long-term strategic retreat. Christian Europe had gone on the offensive at last.