September 23 is a date marked by numerous significant events throughout history, spanning various fields such as science, politics, culture, and more.
From the discovery of a distant planet to pivotal moments in world wars and the rise of influential leaders, this day offers a fascinating glimpse into the past.
In this article, we explore 20 notable events that occurred on September 23, highlighting their impact and legacy.
Join us as we delve into these historical moments, beginning with the earliest in the 14th century and continuing through to contemporary times.
September 23rd – On this Day in History
1338 – The Battle of Arnemuiden

The Battle of Arnemuiden, which took place on September 23, 1338, was the first significant naval engagement of the Hundred Years’ War between England and France. The battle occurred off the coast of Arnemuiden, a port town in the Netherlands.
This confrontation is notable for the use of artillery, as the English ship Christofer was equipped with three cannons, marking one of the earliest known uses of gunpowder weaponry in naval warfare.
Also Read: September 22 Event in History
Despite this technological edge, the English fleet, led by John Kingston, was overwhelmed by the French forces. The French captured the Christofer along with its valuable cargo, delivering a blow to the English and demonstrating the challenges of early naval gunpowder warfare.
1459 – The Battle of Blore Heath
The Battle of Blore Heath, fought on September 23, 1459, was one of the opening battles in the Wars of the Roses, the series of civil wars fought for control of the English throne between the rival houses of Lancaster and York.
This battle took place near Market Drayton in Shropshire. The Yorkist army, commanded by the Earl of Salisbury, was intercepted by a larger Lancastrian force under Lord Audley. Despite being heavily outnumbered, the Yorkists achieved a decisive victory.
Lord Audley was killed in the conflict, and the Lancastrians suffered significant casualties. The victory at Blore Heath bolstered the Yorkist cause, helping to solidify their position in the ongoing struggle for power.
1641 – The Merchant Royal sinks
On September 23, 1641, the English merchant ship Merchant Royal sank off the coast of Land’s End in Cornwall. The ship was laden with a substantial cargo of gold, silver, and other precious items, making it one of the richest treasure ships lost at sea.
Also Read: September 24th – On this Day in History
The Merchant Royal encountered severe weather that caused it to leak, and despite the crew’s efforts to save the vessel, it ultimately sank. The treasure on board was valued at hundreds of millions of pounds in today’s currency.
The wreck of the Merchant Royal has never been found, and its loss has inspired numerous treasure hunts over the centuries, capturing the imagination of many would-be treasure seekers.
1779 – Battle of Flamborough Head
The Battle of Flamborough Head, which took place on September 23, 1779, was a significant naval engagement during the American Revolutionary War.
The American naval commander John Paul Jones led a small squadron, including the USS Bonhomme Richard, against the British warship HMS Serapis, commanded by Captain Richard Pearson.

The battle occurred near Flamborough Head off the coast of Yorkshire, England. Despite the Bonhomme Richard being heavily damaged and on fire, Jones refused to surrender, famously declaring, “I have not yet begun to fight!”
After a fierce battle, Jones and his crew managed to board and capture the Serapis. This victory was a major morale boost for the American cause and established Jones as a legendary figure in naval history.
1803 – The Second Anglo-Maratha War begins
The Second Anglo-Maratha War began on September 23, 1803, marking a significant conflict between the British East India Company and the Maratha Empire in India. The war was triggered by the expansionist policies of the British and internal divisions within the Maratha Empire.
The first major battle of this war was the Battle of Assaye, where British forces, led by Arthur Wellesley (who later became the Duke of Wellington), defeated the Maratha army. This victory was crucial for the British, allowing them to gain a strategic advantage and territorial gains.
The war continued until 1805, culminating in the Treaties of Deogaon and Surji-Anjangaon, which further cemented British dominance in India and significantly weakened Maratha power.
1845 – The Knickerbocker Base Ball Club is founded
On September 23, 1845, the Knickerbocker Base Ball Club was established in New York City. Founded by Alexander Cartwright and a group of baseball enthusiasts, the Knickerbocker Base Ball Club is often credited with formalizing the modern rules of baseball.
Cartwright and his colleagues devised a set of rules that formed the basis of the game as it is known today, including the diamond-shaped infield, the foul lines, and the three-strikes rule.
These innovations helped standardize the game, transforming it from various informal versions played across the country into an organized sport. The founding of the Knickerbocker Club marked a pivotal moment in the history of baseball, laying the groundwork for its evolution into America’s pastime.
1846 – Neptune is discovered
The planet Neptune was discovered on September 23, 1846, by German astronomer Johann Galle, with the assistance of Heinrich d’Arrest, at the Berlin Observatory. The discovery was a significant achievement in the field of astronomy, as it was the first planet located through mathematical predictions rather than direct observation.
French mathematician Urbain Le Verrier had calculated the position of Neptune based on irregularities in the orbit of Uranus, suggesting the presence of another distant planet exerting a gravitational influence.
Following Le Verrier’s calculations, Galle and d’Arrest successfully identified Neptune, confirming the accuracy of the mathematical predictions. This discovery not only added a new planet to our solar system but also validated the power of mathematical analysis in astronomical research.
1862 – Otto von Bismarck is appointed Prime Minister of Prussia
On September 23, 1862, Otto von Bismarck was appointed Prime Minister of Prussia by King Wilhelm I. Bismarck’s appointment marked the beginning of a transformative period in German and European history.

Known for his skillful diplomacy and strong-willed leadership, Bismarck pursued a policy of “realpolitik,” focusing on practical and pragmatic approaches to achieve his goals. He played a crucial role in the unification of Germany, orchestrating a series of wars that ultimately led to the establishment of the German Empire in 1871.
Bismarck’s tenure as Prime Minister and later as the first Chancellor of the German Empire shaped the political landscape of Europe, making him one of the most influential statesmen of the 19th century.
1889 – Nintendo Koppai is founded
Nintendo Koppai, now known as Nintendo Company, Limited, was founded on September 23, 1889, by Fusajiro Yamauchi in Kyoto, Japan. Originally established as a playing card company, Nintendo produced handmade hanafuda cards, which became popular in Japan.
Over the years, Nintendo diversified its business, venturing into various entertainment products and eventually the electronic gaming industry.
The company’s entry into video games in the 1970s and 1980s revolutionized the gaming industry, with iconic products like the Nintendo Entertainment System (NES), Game Boy, and franchises such as Mario, Zelda, and Pokémon.
Today, Nintendo is a global leader in the video game industry, renowned for its innovation and enduring impact on gaming culture.
1905 – Norway and Sweden sign the Karlstad treaty
On September 23, 1905, Norway and Sweden signed the Karlstad Treaty, which peacefully dissolved the union between the two countries. The union, which had been in place since 1814, was marked by growing nationalistic sentiments in Norway and a desire for full independence.
After a series of negotiations, the treaty was signed in the Swedish town of Karlstad, ensuring a peaceful separation. The agreement allowed Norway to become an independent kingdom, while Sweden recognized Norwegian sovereignty.
This peaceful dissolution was a significant achievement in diplomatic history, demonstrating that complex political issues could be resolved through negotiation and compromise rather than conflict. The Karlstad Treaty paved the way for Norway to establish itself as an independent nation on the international stage.
1909 – The Phantom of the Opera is first published
On September 23, 1909, Gaston Leroux’s novel “The Phantom of the Opera” was first published as a serial in the French newspaper Le Gaulois. The story, set in the Paris Opera House, follows a mysterious and disfigured musical genius known as the Phantom who haunts the opera house and falls in love with the beautiful soprano Christine Daaé.
The novel blends elements of romance, mystery, and horror, captivating readers with its atmospheric setting and complex characters.
The Phantom’s tragic love story and haunting presence have inspired numerous adaptations, including Andrew Lloyd Webber’s immensely successful musical. Leroux’s work remains a classic in Gothic literature, influencing countless works in various media.
1932 – The Kingdom of Hejaz and Nejd is renamed the Kingdom of Saudi Arabia
On September 23, 1932, the Kingdom of Hejaz and Nejd was officially renamed the Kingdom of Saudi Arabia by its ruler, Abdulaziz Ibn Saud. This event marked the unification of the various tribal regions under a single national entity, laying the foundation for the modern state of Saudi Arabia.
Abdulaziz, also known as Ibn Saud, had spent years consolidating power, bringing stability to the Arabian Peninsula after decades of tribal conflicts. The unification was a significant step in the establishment of a centralized government and the development of national identity.
Saudi Arabia’s foundation set the stage for its emergence as a key player in regional politics and the global oil industry, given its vast petroleum reserves.
1938 – A time capsule is buried at the World’s Fair in New York
On September 23, 1938, a time capsule intended to be opened 5,000 years later was buried at the site of the World’s Fair in New York. The capsule, created by the Westinghouse Electric & Manufacturing Company, was filled with artifacts intended to provide future generations with a snapshot of contemporary life and technology.
Items included in the capsule ranged from everyday objects like a fountain pen and a woman’s hat to microfilm containing significant documents and news reports.
The time capsule was designed to withstand the test of time, encapsulating the hopes and achievements of the era for posterity. This event reflected the optimism and forward-thinking spirit of the period, as well as a desire to communicate with future generations.
1943 – The USS Harmon is launched

On September 23, 1943, the USS Harmon was launched. This was a significant event in U.S. naval history, as the USS Harmon was the first Navy ship to be named after an African-American.
The ship was named in honor of Leonard Roy Harmon, a Mess Attendant First Class who was posthumously awarded the Navy Cross for his heroic actions during the Battle of Guadalcanal in World War II.
Harmon’s bravery and sacrifice were recognized by naming the ship after him, marking a milestone in the recognition of African-Americans’ contributions to the military. The launch of the USS Harmon was a step forward in acknowledging the service and valor of African-American personnel in the U.S. Navy.
1952 – Richard Nixon delivers the “Checkers speech”
On September 23, 1952, then-Senator Richard Nixon delivered his famous “Checkers speech” on national television. At the time, Nixon was the Republican vice-presidential candidate running with Dwight D. Eisenhower. He had been accused of benefiting from a secret political fund, leading to calls for his resignation from the ticket.
In a masterful use of the new medium of television, Nixon addressed the American public directly, explaining his personal finances and denying any wrongdoing. He famously mentioned his dog Checkers, a gift to his daughters, declaring he would not return it.
The speech was a turning point in political communication, showcasing the power of television to influence public opinion. It successfully garnered public support, allowing Nixon to remain on the Republican ticket, and ultimately contributing to his political career.
1962 – The Lincoln Center for the Performing Arts opens
On September 23, 1962, the Lincoln Center for the Performing Arts officially opened in New York City. This iconic cultural complex, located on the Upper West Side of Manhattan, was designed to be a hub for the performing arts and a symbol of cultural excellence.
The center comprises several world-renowned institutions, including the Metropolitan Opera House, the New York Philharmonic, and the New York City Ballet. Its opening was marked by a gala attended by prominent figures from the arts, politics, and society.
The Lincoln Center has since become a vital part of New York’s cultural landscape, hosting countless performances and events that attract millions of visitors annually. It has played a significant role in promoting the arts, supporting artists, and making high-quality performances accessible to the public.
1973 – Juan Perón returns to power in Argentina
On September 23, 1973, Juan Perón, the former president of Argentina, returned to power after an 18-year exile. Perón, a charismatic and controversial figure, had been ousted from office in 1955 by a military coup.
His return marked a dramatic comeback in Argentine politics, facilitated by the widespread support of the working class and the Peronist movement.
Perón’s third term as president was short-lived; he passed away in July 1974, leaving his third wife, Isabel Perón, as his successor. Juan Perón’s legacy remains deeply influential in Argentina, with Peronism continuing to shape the country’s political landscape. His policies and leadership style have left a lasting impact on Argentine society, economy, and politics.
1980 – Bob Marley plays his final concert
On September 23, 1980, reggae legend Bob Marley performed his final concert at the Stanley Theatre in Pittsburgh, Pennsylvania. At the time, Marley was battling cancer, which had been diagnosed in 1977.
Despite his illness, he continued to tour, driven by his passion for music and his desire to spread his messages of peace, love, and social justice.
The concert in Pittsburgh was part of the Uprising Tour, promoting his album “Uprising.” Marley’s final performance was marked by his powerful stage presence and his commitment to his music and message, even in the face of severe illness. He passed away on May 11, 1981, but his music and legacy continue to resonate worldwide, making him an enduring symbol of reggae and a global cultural icon.
2002 – The first public version of Mozilla Firefox is released
On September 23, 2002, the first public version of the web browser Mozilla Firefox, initially named “Phoenix 0.1,” was released.
Developed by the Mozilla Foundation, Firefox emerged as an open-source alternative to Internet Explorer, which dominated the browser market at the time. Firefox quickly gained popularity due to its speed, security features, and user-friendly interface.
It introduced innovations such as tabbed browsing, which greatly enhanced the user experience. The release of Firefox marked a significant moment in the evolution of the internet, promoting open standards and providing users with a choice beyond the proprietary browsers available. Firefox’s success contributed to the diversification and democratization of web access, shaping the future of internet browsing.
2019 – Greta Thunberg addresses the United Nations Climate Action Summit
On September 23, 2019, Swedish climate activist Greta Thunberg delivered a powerful speech at the United Nations Climate Action Summit in New York City. At just 16 years old, Thunberg had already become an international figure for her environmental activism, starting with her school strike for climate movement, “Fridays for Future.”
In her speech, Thunberg passionately criticized world leaders for their inaction on climate change, famously stating, “How dare you!” She accused them of failing future generations and called for urgent and concrete measures to combat the climate crisis.
Thunberg’s address at the UN significantly amplified her voice and the global youth climate movement, drawing widespread attention to the urgency of addressing climate change and inspiring millions to take action.