February – In England, Dr. Richard Lower performs the first blood transfusion between animals. According to his account to the Royal Society journal Philosophical Transactions in December, Dr. Lower "towards the end of February... selected one dog of medium size, opened its jugular vein, and drew off blood, until its strength was nearly gone. Then, to make up for the great loss of this dog by the blood of a second, I introduced blood from the cervical artery of a fairly large mastiff, which had been fastened alongside the first, until this latter animal showed it was overfilled by the inflowing blood." [1]
March 6 – The Philosophical Transactions of the Royal Society of London begins publication in England, the first scientific journal in English and the oldest to be continuously published.
March 11 – A new legal code is approved for the Dutch and English towns of New York, guaranteeing all Protestants the right to continue their religious observances unhindered.
March 16 – Bucharest allows Jews to settle in the city, in exchange for an annual tax of 16 guilders.
April–June
April 12 – The burial of Margaret Porteous is recorded; hers is the first known death during the Great Plague of London. This last major outbreak of Bubonic plague in the British Isles has possibly been introduced by Dutchprisoners of war. Two-thirds of Londoners leave the city, but over 68,000 die. The plague spreads to Derbyshire.
June 11 – Shivaji, leader of the Bhonsale clan of the Marathas in India, signs the Treaty of Purandar with the Mughal Empire, giving up 23 of the 35 forts under his control, agreeing to pay reparations to the Mughal Emperor Aurangzeb, and sending his son to stay as a hostage at Agra.
June 12 – England installs a municipal government in New York City (the former Dutch settlement of New Amsterdam).
July 3 – The first documented case of cyclopia is diagnosed in a horse.
July 7 – King Charles II of England leaves London with his entourage, fleeing the Great Plague. He moves his court to Salisbury, then Exeter.
July 9 – The colonization of the south Indian Ocean island Réunion begins, with the Compagnie des Indes Orientales sending 20 permanent settlers, under the command of Etienne Regnault, from the French ship Taureau.[3]
July 11 – Pierre de Beausse, an envoy of France's King Louis XIV, formally claims possession of the African island of Madagascar on behalf of the French East India Company after landing on the coast in the 32-gun frigate Saint-Paul.[4]
August 27 – Ye Bare & Ye Cubbe, the first play in English in the American colonies, is given its first performance. The presentation takes place at Cowles Tavern in Pungoteague, Virginia.[7] The event is documented in 1958 in a historical marker with the heading "The Bear and the Cub" which says "This first play recorded in the United States was presented August 27, 1665. The Accomack County Court at Pungoteague heard charges against three men 'for acting a play,' ordered inspection of costumes and script, but found the men 'not guilty.'"[8]
^"The history of peripheral intravenous catheters: How little plastic tubes revolutionized medicine", By A. M. Rivera, et al., Acta Anaesthesiologica Belgica 56 (2005) p. 272-273
^Mahoney, Michael (1994). The mathematical career of Pierre de Fermat, 1601-1665. Princeton, N.J: Princeton University Press. p. 17. ISBN9780691036663.
^Villari, Rosario (1995). Baroque personae. Chicago: University of Chicago Press. p. 218. ISBN9780226856377.
^Saenredam, Pieter (2000). Pieter Saenredam, the Utrecht work : paintings and drawings by the 17th-century Master of Perspective. Utrecht: Centraal Museum. p. 14. ISBN9789073285750.
^Spielman, John (1977). Leopold I of Austria. New Brunswick, N.J: Rutgers University Press. p. 46. ISBN9780813508368.
^Rubin, Davida (1991). Sir Kenelm Digby, F.R.S., 1603-1665 : a bibliography based on the collection of K. Garth Huston Sr., M.D. San Francisco: J. Norman. p. xiii. ISBN9780930405298.
^Brigstocke, Hugh (1993). Italian and Spanish paintings in the National Gallery of Scotland. Edinburgh: Trustees of the National Galleries of Scotland. p. 151. ISBN9780903598224.
^Baker, Christopher (2002). Absolutism and the scientific revolution, 1600-1720: a biographical dictionary. Westport, Conn: Greenwood Press. p. 302. ISBN9780313308277.
^The New Encyclopaedia Britannica. Encyclopaedia Britannica. 2003. p. 300.