March 22 – Greece receives autonomy from the Ottoman Empire in the London Protocol, signed by Russia, France and Britain, effectively ending the Greek War of Independence. Greece continues to seek full independence through diplomatic negotiations with the three Great Powers.
June 3 – The Swan River Colony (later to become the cities of Perth and Fremantle) is founded in Western Australia. This secures the western third of the Australian landmass for the British.
June 19 – Robert Peel establishes the Metropolitan Police Service in London, the first modern police force. The first officers, known by the nickname "bobbies", go on patrol on September 29.
August 12 – Mrs. Helen Dance, wife of the captain of the ship Sulphur, cuts down a tree to mark the founding day of the town of Perth, Western Australia.
June 27 – James Smithson, British mineralogist, chemist, whose fortune eventually went to the United States of America, and was used to initially fund the Smithsonian Institution (b. 1764)
↑"Suttees, or the Burning of Widows", in The World's Progress: A Dictionary of Dates, ed. by George P. Putnam and F. B. Perkins (G. P. Putnam's Sons, 1878) p604.