- Jan 27 Dorothea von Benckendorff, Baltic monarch of Lieven, dies at 72
- Feb 7 Félix de Merode, Earl of Merode, Belgian minister of War, dies at 65
- Feb 9 Dionysios Solomos, Greek poet of the Greek national anthem (b. 1798)
- Feb 10 David Thompson, Canadian explorer (b. 1770)
- Feb 16 Auguste-Gaspard-Louis Desnoyers, French engraver, dies at 77
- Feb 16 Elisha Kent Kane, Arctic explorer (Kane Basin), dies at 37
- Feb 28 André Dumont, Belgian geologist, dies at 48
- Mar 11 Manuel Jose Quintana, Spanish author and poet (A la paz), dies at 84
- Mar 21 Abraham J van der Aa, lexicographer (Biograph dictionary), dies at 64
- Mar 26 Wei Yuan, Chinese scholar and geographer of Qing Dynasty, dies at 62
- Apr 8 Mangal Pandey, Indian soldier (b. 1827)
- Apr 30 Princess Mary, Duchess of Gloucester and Edinburgh, dies at 81
- May 2 LC Alfred the Musset, French poet (Lesson caprices Marianne), dies
- May 11 E Francois Vidocq, French criminalogist/police officer, dies at 81
- May 23 Augustin Louis Cauchy, French mathematician and physicist, dies at 67
- Jun 8 Douglas William Jerrold, British playwright and satirist (b. 1803)
- Jun 19 Alexander Twilight, American politician and minister, first African American to graduate and hold political office, dies at 61
- Jun 30 Alcide d'Orbigny, French naturalist, dies at 54
- Jul 2 Carlo Pisacane, Italian patriot (b. 1818)
- Jul 4 William L. Marcy, American statesman (b. 1786)
- Jul 16 Pierre-Jean de Baranger, poet, dies
- Jul 19 Stefano Franscini, Swiss Federal Councilor (b. 1796)
- Jul 25 Joseph Napoleon Ney, French politician, dies at 54
- Jul 29 Charles Lucien Bonaparte, French prince of Canino and Musignano, dies at 54
- Jul 29 Thomas Dick, Scottish scientific teacher and writer (b. 1774)
- Aug 1 Charles Turner, engraver, dies
- Aug 3 Eugène Sue, French novelist (b. 1804)
- Aug 10 John Wilson Croker, politician
- Aug 12 William Daniel Conybeare, geologist, dies
- Aug 27 Rufus Wilmot Griswold, American poet, literary critic and editor, dies of tuberculosis at 42
- Sep 3 M Heinrich C Lichtenstein, German zoologist/explorer, dies at 77
- Sep 3 John McLoughlin, Canadian trapper (b. 1784)
- Sep 5 Auguste Comte, French sociologist (b. 1798)
- Oct 28 Louis Eugène Cavaignac, French soldier and politician (b. 1802)
- Nov 24 Henry Havelock, British soldier (War in Afghanistan 1838-39), dies at 62
- Nov 26 Joseph Freiherr von Eichendorff, German poet (That Freier), dies at 69
- Dec 3 Christian D Rauch, German sculptor, dies at 80