| 40771 | April 9 | Event | 2003 – Iraq War: Baghdad falls to American forces Iraqis turn on symbols of their former leader Saddam Hussein, pulling down a grand statue of him and tearing it to pieces. |
| 40772 | April 9 | Event | 2005 – Charles, Prince of Wales marries Camilla Parker Bowles in a civil ceremony at Windsor's Guildhall. |
| 40773 | April 9 | Event | 2009 – In Tbilisi, Georgia, up to 60,000 people protest against the government of Mikheil Saakashvili. |
| 40774 | April 9 | Event | 2013 – A 6.1–magnitude earthquake strikes Iran killing 32 people and injuring over 850 people. |
| 40775 | April 9 | Event | 2013 – At least 13 people are killed and another three injured after a man goes on a spree shooting in the Serbian village of Velika Ivanča. |
| 40776 | April 9 | Event | 2014 – A student stabs 20 people at Franklin Regional High School in Murrysville, Pennsylvania. |
| 40777 | April 9 | Birth | 1498 – Jean, Cardinal of Lorraine (d. 1550) |
| 40778 | April 9 | Birth | 1597 – John Davenport, English minister, co-founded the New Haven Colony (d. 1670) |
| 40779 | April 9 | Birth | 1598 – Johann Crüger, German composer and theorist (d. 1662) |
| 40780 | April 9 | Birth | 1627 – Johann Caspar Kerll, German organist and composer (d. 1693) |
| 40781 | April 9 | Birth | 1634 – Countess Albertine Agnes of Nassau (d. 1696) |
| 40782 | April 9 | Birth | 1648 – Henri de Massue, Earl of Galway, French soldier and diplomat (d. 1720) |
| 40783 | April 9 | Birth | 1649 – James Scott, 1st Duke of Monmouth, Dutch-English general and politician, Lord Lieutenant of Staffordshire (d. 1685) |
| 40784 | April 9 | Birth | 1680 – Philippe Néricault Destouches, French playwright (d. 1754) |
| 40785 | April 9 | Birth | 1686 – James Craggs the Younger, English politician, Secretary of State for the Southern Department (d. 1721) |
| 40786 | April 9 | Birth | 1691 – Johann Matthias Gesner, German scholar and academic (d. 1761) |
| 40787 | April 9 | Birth | 1717 – Georg Matthias Monn, Austrian organist, composer, and educator (d. 1750) |
| 40788 | April 9 | Birth | 1770 – Thomas Johann Seebeck, German physicist and academic (d. 1831) |
| 40789 | April 9 | Birth | 1773 – Étienne Aignan, French author and academic (d. 1824) |
| 40790 | April 9 | Birth | 1794 – Theobald Boehm, German flute player and composer (d. 1881) |
| 40791 | April 9 | Birth | 1802 – Elias Lönnrot, Finnish physician and philologist (d. 1884) |
| 40792 | April 9 | Birth | 1806 – Isambard Kingdom Brunel, English engineer, designed the Clifton Suspension Bridge (d. 1859) |
| 40793 | April 9 | Birth | 1807 – James Bannerman, Scottish theologian and academic (d. 1868) |
| 40794 | April 9 | Birth | 1821 – Charles Baudelaire, French poet and critic (d. 1867) |
| 40795 | April 9 | Birth | 1830 – Eadweard Muybridge, English photographer and cinematographer (d. 1904) |
| 40796 | April 9 | Birth | 1835 – Leopold II of Belgium (d. 1909) |
| 40797 | April 9 | Birth | 1835 – Somerset Lowry-Corry, 4th Earl Belmore (d. 1913) |
| 40798 | April 9 | Birth | 1846 – Paolo Tosti, Italian-English composer and educator (d. 1916) |
| 40799 | April 9 | Birth | 1865 – Erich Ludendorff, German general and politician (d. 1937) |
| 40800 | April 9 | Birth | 1865 – Charles Proteus Steinmetz, Polish-American mathematician and engineer (d. 1923) |