Template:On this day - December 31

Miguel de Unamuno

• 1229 – The city of Palma de Mallorca (present-day Spain), which was in the hands of the Muslims, is conquered by James I the Conqueror.
• 1431 – In the Sultanate of Granada (present-day Spain), Yusuf IV is proclaimed sultan after a popular uprising dethrones Muhammad IX.
• 1556 – In Spain, the sub-Saharan humanist and poet Juan Latino receives the chair of grammar and Latin language at the University of Granada.
• 1584 – In Spain, Philip II signs with the Catholic League, led by Henry of Guise, the Treaty of Joinville, by which they undertake to expel the Protestants.
• 1588 – Death of Luis de Granada, Spanish religious and writer (b. 1504).
• 1658 – Birth of Juan de Cabrera, Spanish Jesuit theologian, philosopher and writer (d. 1730).
• 1784 – In Spain, Charles III establishes the penalty of the galleys to strengthen the fight against pirates.
• 1812 – In the Viceroyalty of the Río de la Plata, the Battle of Cerrito takes place between the royalist forces holding the city of Montevideo and the pro-independence forces of the Buenos Aires government besieging it.
• 1844 – In the Philippines, the Gregorian calendar is adopted, so this day did not exist: Tuesday 30 December (which in the Philippines was Monday) was followed by Wednesday 1 January 1845.
• 1874 – In Spain, a provisional government is formed under the direction of Antonio Cánovas del Castillo after the Pronunciamiento of Sagunto by the soldier Arsenio Martínez Campos, and the restoration of the monarchy is decreed, after the adherence of Fernando Primo de Rivera.
• 1913 – In Spain, the Ministry of the Interior establishes censorship of film material.
• 1936 – Death of Miguel de Unamuno, Spanish writer and philosopher of the Generation of '98 (b. 1864).
• 1958 – In Havana (Cuba), the dictator Fulgencio Batista is expelled. The revolutionary Government of Fidel Castro begins.
• 1998 – Last day of the national currencies of the first eleven countries of the eurozone as independent systems; the next day the euro enters the financial markets as a unit of account.
• 1999 – The United States hands over the administration of the Panama Canal to the Republic of Panama.
• 1999 – The 20th century and the 2nd millennium come to an end.
• 2004 – Death of Raúl Matas, Chilean journalist, television presenter and radio announcer (b. 1921).
• 2008 – Death of Julio Nieto Bernal, Colombian journalist and radio announcer (b. 1935).