» Also see: number 1440. Year 1440 was a leap year starting on Friday (link will display the full calendar) of the Julian calendar. Events of 1440 February 21 - The Prussian Confederation is formed. September 13 - Gilles de Rais is taken into custody upon an accusation brought against him by the Bishop of Nantes. October 22 - Gilles de Rais confesses and is sentenced to death. Undated Itzcóatl, Aztec ruler of Tenochtitlan, dies and is succeeded by Moctezuma I (Moctezuma Ilhuicamin… (More on 1440)