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Explore the historical events that shaped our world on September 23rd. From major milestones to cultural achievements, see what happened on this day in history. Dates for earlier events may be approximate.
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The Battle of Clontarf takes place near Dublin, Ireland, where the forces of Brian Boru, High King of Ireland, defeat the Viking forces of Dublin and their allies, although Brian Boru is killed in the battle. The battle marked the end of the large-scale Viking attempts to conquer Ireland and leading to the decline of Viking power on the island.
The Concordat of Worms is signed on September 23, 1122, in the city of Worms, Germany, by Pope Callixtus II and Holy Roman Emperor Henry V, taking a significant step in separating church and state and bringing a peaceful end to a major power struggle between the papacy and the Holy Roman Empire.
The compromise agreement resolved the long standing Investiture Controversy conflict over the right to appoint church officials, establishing the pope having the sole right to appoint them and the emperor having the authority to grant them secular power with the symbols of secular authority, such as land and titles.
The Battle of the Puig takes place during the Reconquista, where forces of the Kingdom of Aragon defeat the Almohad Caliphate in Valencia, Spain.
The Battle of Blore Heath takes place during the Wars of the Roses in England, where the Yorkist forces, led by Richard Neville, defeat the Lancastrians.
John Paul Jones, commanding the U.S. ship Bonhomme Richard, an armed former French East India Company trading vessel which had been adapted for military use, wins the naval Battle of Flamborough Head, against the British ships of war Countess of Scarborough and Serapis, off the the coast of Yorkshire, England. The Americans suffered approximately 170 casualties, while the British suffered approximately 117 casualties and 2 captured ships. More
The Lewis and Clark Expedition, also known as the Corps of Discovery, returns to St. Louis after a 28-month journey to the Pacific Ocean completing their journey to explore and map the western portion of the United States.
The explorers were met with a hearty welcome from the town's inhabitants, who gathered to celebrate their safe arrival and the successful completion of the first recorded round-trip overland crossing of North America.
Astronomer Johann Gottfried Galle is the first to identify Neptune as the eighth planet orbiting around the Sun. The discovery was made possible by mathematical calculations of its predicted position due to observed perturbations in the orbit of the planet Uranus. A telescope was then used since Neptune is too faint and distant to be visible to the naked eye.
Astronomers soon discovered a moon orbiting Neptune, but it took more than a century to discover a second one. Our knowledge of distant Neptune greatly increased from the scientific observations made during Voyager 2’s flyby in 1989, including the discovery of five additional moons and confirmation of dark rings orbiting the planet. More
Prince Faisal, On Ibn Saud's behalf, declares the unification of the two kingdoms of Hejaz and Nejd as the Kingdom of Saudi Arabia. That date is now a national holiday called Saudi National Day.
Standard Oil geologists' Robert P. “Bert” Miller and Schuyler B. “Krug” Henry, arrive in Saudi Arabia and are the first geologists to enter Saudi Arabia. They came ashore in Al Hasa on Sept. 23,1933 – just two years after the United States officially recognized Ibn Sa’ud’s nation.
US President Truman announces that the Soviet Union had tested a nuclear device several weeks earlier. The White House did not explain how the United States had detected the test, which had occurred on 29 August 1949 at Semipalatinsk, in northeastern Kazakhstan. More
he television series "The Mickey Mouse Club" premieres on American television, becoming an iconic part of popular culture.
Greta Thunberg, the Swedish climate activist, delivers an emotional speech at the United Nations Climate Action Summit, condemning world leaders for their “betrayal” of young people through their inertia and lack of meaningful action action over the climate crisis. She was Sixteen year-old at the time. More
