Template:On this day - April 4

Carolus Clusius

• 636 – Death of Saint Isidore of Seville, Hispano-Gothic Catholic churchman and polymath scholar, Patron of Hispanopedia (b. c. 560).
• 1284 – Death of Alfonso X the Wise, king of the Crown of Castile, León and the other kingdoms in whose titles he styled himself (b. 1221).
• 1305 – Death of Joan I, Queen of Navarre (b. 1273).
• 1541 – In Spain, Saint Ignatius of Loyola is elected first Superior General of the Society of Jesus.
• 1609 – Death of Carolus Clusius, Flemish physician, botanist and naturalist.
• 1566 – In Spain, King Philip II grants the village of Garciaz the title of "Very Illustrious Town".
• 1609 – In Spain, the General Council of the Kingdom of Valencia takes the decision to expel the Moriscos, but the agreement was not made public immediately in order to keep the preparations secret.
• 1640 – Birth of Gaspar Sanz, Spanish composer and guitarist (d. 1710).
• 1823 – In the province of Buenos Aires (Argentina), Brigadier Martín Rodríguez founds the city of Tandil.
• 1847 – In Barcelona (Spain), the Gran Teatro del Liceo is inaugurated.
• 1868 – Birth of Felipe Calderón y Roca, Filipino Spanish-speaking lawyer, politician and intellectual (d. 1908).
• 1888 – Death of José Eleuterio González "Gonzalitos", Mexican physician, politician, writer, educator, historian and philanthropist (b. 1813).
• 1910 – In Madrid (Spain), work begins on the Gran Vía.
• 1913 – Birth of Santiago Antúnez de Mayolo, Peruvian politician, lawyer, historian, researcher and professor.
• 1926 – After crossing the South Atlantic, the Spanish crew of the seaplane Plus Ultra return in triumph.
• 1954 – In Nicaragua, a rebellion of former members of the National Guard and civilians against the dictatorship of General Anastasio Somoza García fails when they try to ambush him on the Carretera Sur. The plan failed because of the betrayal of one of the members of the group, leading to the capture, torture and murder of those involved in the plot.
• 1963 – In Buenos Aires (Argentina), the Army High Command issues communiqué no. 179: "The return of Perón is impossible".
• 2019 – Death of Alberto Cortez, Argentine singer-songwriter and poet (b. 1940).
• 2020 – Death of Luis Eduardo Aute, Hispano-Filipino musician, singer-songwriter, filmmaker, sculptor, painter and poet (b. 1943).
• 2020 – Death of Rafael Leonardo Callejas, economist and politician, President of Honduras between 1990 and 1994 (b. 1943).