- Apr 4 Queen Maria II of Portugal, Daughter of Emperor Pedro I of Brazil, born in Palace of São Cristóvão, Rio de Janeiro, Kingdom of Brazil (d. 1853)
- Apr 6 Johann A H Scheler, Belgian librarian
- Apr 7 Hubert Leonard, composer
- Apr 14 Charles Hallé, Anglo-German pianist, conductor and founder (Halle Orchestra), born in Hagen, Westphalia (d. 1895)
- Apr 18 Carlos Manuel de Céspedes, Cuban revolutionary hero, born in Bayamo, Spanish Cuba (d. 1874)
- Apr 18 Franz von Suppé, Austrian composer (Poet und Bauer), born in Spalato, Dalmatia, Austrian Empire (d. 1895)
- Apr 28 Ezra Abbot, American Bible scholar, born in Jackson, Maine (d. 1884)