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.

1848 – The first Women's Rights Convention in Seneca Falls, New York, a two-day event, concludes.1831 – Seneca and Shawnee people agree to relinquish their land in western Ohio for 60,000 acres west of the Mississippi River.1810 – Citizens of Bogotá, New Granada declare independence from Spain.1807 – Nicéphore Niépce is awarded a patent by Napoleon for the Pyréolophore, the world's first internal combustion engine, after it successfully powered a boat upstream on the river Saône in France.1799 – Tekle Giyorgis I begins his first of six reigns as Emperor of Ethiopia.1738 – Canadian explorer Pierre Gaultier de Varennes et de La Vérendrye reaches the western shore of Lake Michigan.1715 – Seventh Ottoman–Venetian War : The Ottoman Empire captures Nauplia, the capital of the Republic of Venice 's ' Kingdom of the Morea ', thereby opening the way to the swift Ottoman reconquest of the Morea.

1705 – A fire in Oulu, Finland almost completely destroyed the fourth district, which covered the southern part of the city and was by far the largest of the city districts.

1592 – During the first Japanese invasion of Korea, Japanese forces led by Toyotomi Hideyoshi captured Pyongyang, although they were ultimately unable to hold it.

1402 – Ottoman-Timurid Wars: Battle of Ankara : Timur, ruler of Timurid Empire, defeats forces of the Ottoman Empire sultan Bayezid I.

1398 – The Battle of Kellistown was fought on this day between the forces of the English led by Roger Mortimer, 4th Earl of March against the O'Byrnes and O'Tooles under the command of Art Óg mac Murchadha Caomhánach, the most powerful Chieftain in Leinster.

A Dominican named Guala is responsible for the negotiations.

1225 – Treaty of San Germano is signed at San Germano between Holy Roman Emperor Frederick II and Pope Gregory IX.

1189 – Richard I of England officially invested as Duke of Normandy.

792 – Kardam of Bulgaria defeats Byzantine Emperor Constantine VI at the Battle of Marcellae.

The Roman army is drawn into street fights with the Zealots.

70 – Siege of Jerusalem : Titus, son of emperor Vespasian, storms the Fortress of Antonia north of the Temple Mount.July 20 is the 201st day of the year (202nd in leap years ) in the Gregorian calendar 164 days remain until the end of the year.

Apollo 4 combustion instability