Template:On this day - September 18

Pedro Enríquez de Acevedo

• 1502 – Christopher Columbus reaches Costa Rica on his fourth and last voyage.
• 1525 – Birth of Pedro Enríquez de Acevedo, Spanish military officer and politician (d. 1610).
• 1544 – Francis I of France and Charles I of Spain (Holy Roman Emperor) sign the Peace of Crépy, which marked Charles's exit from the Italian War of 1542–1546.
• 1546 – The Battle of Iñaquito takes place, pitting the rebel forces of Gonzalo Pizarro against the soldiers loyal to the Viceroy of Peru, Blasco Núñez Vela.
• 1624 – Death of Pedro Osores de Ulloa, Spanish military officer who, already in his eighties, held the office of governor and president of the Real Audiencia of Chile (b. 1540).
• 1714 – In Spain, the capitulation of Cardona takes place in the War of the Spanish Succession.
• 1810 – In Santiago de Chile, the First Government Junta meets, the first step toward independence, and today celebrated as the date of the Fiestas Patrias in Chile.
• 1832 – In Mexico, the Battle of El Gallinero takes place, in which the rebels of the Zacatecas troops commanded by José Esteban Moctezuma were defeated by the presidential forces commanded by the conservative Vice President Anastasio Bustamante.
• 1838 – The Battle of Matucana takes place, a clash during the War against the Peru-Bolivian Confederation.
• 1838 – The Ecuadorian José Rodríguez Labandera sails the first Hispanic American submarine, called "Hipopótamo".
• 1863 – Death of Pedro Calvo Asensio, Spanish politician, pharmacist, journalist and playwright (b. 1821).
• 1913 – Death of Rosendo García-Ramos y Bretillard, Spanish scientist and archaeologist (b. 1835).
• 1928 – Juan de la Cierva makes his first flight across the English Channel aboard his autogyro.
• 1960 – Fidel Castro arrives in New York as head of Cuba's delegation to the United Nations.
• 1968 – In Mexico, 10,000 army soldiers occupy the Ciudad Universitaria of the UNAM, arresting several students and leaders of the student movement. There are several dead and missing.
• 1980 – The Cuban Arnaldo Tamayo becomes the first Hispanic American and the first person of African descent to fly into space, aboard the Soviet spacecraft Soyuz-38.
• 2003 – Death of Eugenio Marcano, Dominican botanist, entomologist, herpetologist, speleologist and researcher (b. 1923).
• 2012 – Death of Santiago Carrillo, Spanish journalist and politician, secretary general of the Communist Party of Spain (PCE) (b. 1915).
• 2021 – Death of Mario Camus, Spanish film director and screenwriter (b. 1935).