July 20, 0514 Pope Hormisdas assumes.Roman Catholic Church. 
- July 20, 1402 “Ottoman-Timurid Wars: Battle of Ankara – Timur, ruler of Timurid Empire, defeated forces of the Ottoman Empire sultan Bayezid I.”
- July 20, 1656 Swedish forces under the command of King Charles X Gustav defeats the forces of the Polish-Lithuanian Commonwealth at the Battle of Warsaw.
- July 20, 1712 The Riot Act takes effect in Great Britain.
- July 20, 1738 North America: French explorer Pierre Gaultier de Varennes et de la Vrendrye reaches the western shore of Lake Michigan.
- July 20, 1773 “Scottish settlers arrive at Pictou, Nova Scotia (Canada)”
- July 20, 1810 “Citizens of Bogot, New Granada declare independence from Spain.”
- July 20, 1810 Colombia declared independence from Spain
- July 20, 1861 “1864 – American Civil War: Battle of Peachtree Creek – Near Atlanta, Georgia, Confederate forces led by General John Bell Hood unsuccessfully attack Union troops under General William T. Sherman.”
- July 20, 1861 “Confederate state’s congress began holding sessions in Richmond, Va”
- July 20, 1864 Battle of Peachtree Creek-Atlanta Campaign
- July 20, 1866 “Austro-Prussian War: Battle of Lissa – The Austrian Navy , led by Admiral Wilhelm von Tegetthoff, defeats the Italian Navy near the island of Vis in the Adriatic Sea.”
- July 20, 1868 The first use of tax stamps on cigarettes
- July 20, 1871 “British Columbia is admitted to the Dominion of Canada. One of the conditions of entry is that the Dominion Government should, within two years from the date of union, commence the construction of a railway from the Pacific towards the Rocky Mountains and from a point east of the Rocky Mountains towards the Pacific to connect the seaboard of British Columbia with the railway system of Canada. Sir Sandford Fleming was appointed Engineer-in-Chief of this railway which was to be completed by 1881.”
- July 20, 1871 British Columbia joins the confederation of Canada.
- July 20, 1872 Mahlon Loomis receives patent for wireless … the radio is born
- July 20, 1872 The US Patent Office awards the first patent for wireless telegraphy to Mahlon Loomis.
- July 20, 1877 “Rioting in Baltimore, Maryland by Baltimore and Ohio Railroad workers is put down by the state militia, resulting in nine deaths.”
- July 20, 1878 The first telephone introduced in Hawaii
- July 20, 1881 “Indian Wars:Sioux Chief Sitting Bull leads the last of his fugitive people in surrender to US troops at Fort Buford, North Dakota”
- July 20, 1881 “Sioux Indian leader Sitting Bull, surrenders to federal troops”
- July 20, 1885 The Football Association legalises professionalism in football under pressure from the British Football Association.