July 18

• July 18, 390 BC
  Gauls decisively defeat Roman forces and inflict heavy casualties on Romans at the battle of Allia
• July 18, 1858
  The summer Great Stink takes place when the smell of untreated sewage almost overwhelmed people in central London, England
• July 18, 1872
  Britain introduced the Ballot Act for voting by secret ballot
• July 18, 1925
  Mein Kampf, an autobiographical manifesto outlining future plans for Germany, is published by Nazi leader Adolf Hitler
• July 18, 1936
  General Francisco Franco leads uprising in Spanish Morocco starting Spanish Civil War between Republican, loyal to the democratic Spanish Republic, and Nationalist forces backed by Nazi Germany and Fascist Italy
• July 18, 1995
  Eruption of Soufrière Hills volcano in the southern part of Montserrat, a British overseas territory in the Caribbean, destroys Montserrat's capital city of Plymouth and leads to emigration of two-thirds of the island's population
• July 18, 2003
  Second Congo War ends with more than 5 million dead

June 30

• June 30, 827
  The allied fleets of Muslims lands in southwestern Sicily beginning the Muslim conquest of Sicily
• June 30, 1097
  The Crusaders defeat the Turks at Battle of Dorylaeum
• June 30, 1520
  Moctezuma II is murdered by the Aztec as Spanish conquistadors under Cortez fled the Aztec capital of Tenochtitlan during the night and begin to plunder gold
• June 30, 1859
  French acrobat Charles Blondin crosses Niagara Falls on a tightrope as 5,000 spectators watch
• June 30, 1893
  Excelsior Diamond, the second largest rough diamond of gem quality ever found, is discovered at the Jagersfontein Mine in South Africa
• June 30, 1894
  Tower Bridge, a combined bascule and suspension bridge in London which crosses the River Thames, is opened
• June 30, 1908
  The Tunguska event near Tunguska River in central Siberia, Russia, later conjectured to be a meteorite strike, explodes 5-10 km above the forest and devastates thousands of square kilometers of Siberia
• June 30, 1923
  New Zealand claims Ross Dependency in Antarctica
• June 30, 1960
  Belgian Congo gains independence from Belgium as Republic of the Congo, triggering Congo Crisis, a conflict between nationalist faction under Prime Minister Patrice Lumumba and leader of country Mobutu Sese Seko
• June 30, 1963
  Cardinal Montini elected Pope Paul VI, 262nd head of Roman Catholic Church
• June 30, 1971
  Three cosmonauts die as Soyuz 11 depressurizes during reentry
• June 30, 1997
  Collapse of the currency of Thailand sparks the 1997 Asian Financial Crisis
• June 30, 2002
  Brazil national football team wins its fifth championship at the FIFA World Cup, held in South Korea and Japan