Template:On this day - September 4

Bermudo III of León

• 1037 – Bermudo III, King of León, dies in combat from sixteen lance wounds, every one of them mortal (b. 1017).
• 1479 – The Treaty of Alcáçovas is signed between the Catholic Monarchs on one side and King Afonso V of Portugal and his son John on the other.
• 1520 – Hernán Cortés conquers the Aztec city of Tepeaca and founds the Villa de Segura de la Frontera.
• 1535 – The pirate Barbarossa attacks and sacks the city of Mahón on the island of Menorca (Spain).
• 1736 – Birth of Cándido María Trigueros, Spanish writer, translator and playwright (d. 1798).
• 1781 – In New Spain, the Spaniards Gaspar de Portolá and Junípero Serra found the Pueblo de la Reina de los Ángeles (today the city of Los Angeles, California).
• 1821 – In the town square of Mendoza (Argentina), the Chilean general José Miguel Carrera is executed by firing squad.
• 1902 – In Buenos Aires (Argentina), during the ceremony exhuming the remains of General Manuel Belgrano, the Minister of War, Pablo Riccheri, and the Minister of the Interior, Joaquín V. González, steal several teeth. They are forced to return them under pressure from the Buenos Aires newspapers.
• 1922 – Death of Amós Salvador Rodrigáñez, Spanish engineer and politician (b. 1845).
• 1933 – In Cuba, Ramón Grau San Martín comes to power and imposes a government directed by Fulgencio Batista.
• 1970 – In Chile, Salvador Allende, socialist candidate of Popular Unity, wins the presidential election.
• 1990 – In Chile, with the return of democracy, President Patricio Aylwin orders a state funeral for former President Salvador Allende on the 20th anniversary of his election.
• 1993 – In Nicaragua, Cardinal Miguel Obando inaugurates the new Managua Cathedral, designed by the Mexican architect Ricardo Legorreta.
• 2004 – Death of Jorge Enea Spilimbergo, Argentine politician, writer and ideologue, founder of the National Left (b. 1928).
• 2010 – Death of Olga Gallego Domínguez, Spanish historian, archivist, academic and writer (b. 1923).
• 2011 – Death of Carlos Ballesteros, Spanish actor and stage director (b. 1936).
• 2011 – Death of Juan Alsina, Spanish naval engineer and politician (b. 1942).
• 2013 – Death of María Teresa Rodríguez, Mexican pianist, the first woman to direct the National Conservatory of Music (b. 1923).