1170day.year
Anglo-Norman invasion of Ireland: The Kingdom of Dublin falls to Anglo-Norman invaders.
On September 21, 1170, Anglo-Norman forces captured the Kingdom of Dublin, marking a crucial step in the Norman conquest of Ireland.
In the summer of 1170, Anglo-Norman knights under Richard de Clare sought to extend their influence across Ireland. After landing in Ireland earlier that month, they advanced on Dublin, the richest and most fortified Norse-Gaelic city. On September 21, a combined force of Norman knights and Irish allies breached the city defenses. The fall of Dublin provided the Normans with a strategic coastal stronghold and a base for further operations. The capture altered power relations on the island, signaling the beginning of centuries of Norman and later English involvement in Ireland. Local Irish kings would struggle to resist the Normans, leading to profound political and cultural changes. The event laid foundations for the complex Anglo-Irish history that would shape the region for generations.
1170
Anglo-Norman invasion of Ireland
Kingdom of Dublin
Anglo-Norman
1217day.year
Livonian Crusade: The Estonian leader Lembitu and Livonian leader Caupo of Turaida are killed in the Battle of St. Matthew's Day.
During the Livonian Crusade, the allied pagan leaders Lembitu and Caupo of Turaida died in the Battle of St. Matthew's Day in 1217.
The Livonian Crusade sought to convert Baltic tribes to Christianity under the auspices of the Teutonic Knights. Estonian leader Lembitu, a unifying figure among the tribes, and Livonian chief Caupo of Turaida, an early Christian convert, met on the battlefield on September 21, 1217. Despite their divergent beliefs, the two leaders had formed a temporary alliance to resist German crusaders. The battle, fought on St. Matthew's Day, ended in a decisive defeat, and both leaders were killed in combat. Their deaths marked a turning point, weakening native resistance and accelerating the Christianization and political subjugation of the Baltic peoples. The aftermath saw the expansion of Germanic rule and the establishment of ecclesiastical states that would endure for centuries. The event highlights the complex interplay of faith, power, and identity in medieval Northern Europe.
1217
Livonian Crusade
Lembitu
Caupo of Turaida
Battle of St. Matthew's Day
1745day.year
A British government army led by Sir John Cope is defeated in less than 15 minutes by the Jacobite forces of Prince Charles Edward Stuart.
On September 21, 1745, the Jacobite army under Prince Charles Edward Stuart overwhelmed Sir John Cope's forces at the Battle of Prestonpans in under fifteen minutes.
The skirmish at Prestonpans marked the opening clash of the Jacobite rising of 1745. Sir John Cope, commanding roughly 1,500 government troops, faced a similar number of Highland Jacobites racing south toward Edinburgh. On the morning of September 21, the Jacobites executed a surprise bayonet charge across marshy ground, catching Cope's men off guard. In less than fifteen minutes, the government line collapsed, yielding a decisive Jacobite victory. The rout boosted Highland morale and enabled Charles Edward Stuart, known as the Young Pretender, to occupy Edinburgh shortly thereafter. Though the uprising ultimately ended in defeat at Culloden in 1746, Prestonpans demonstrated the formidable spirit of the Jacobite clans. The event has since been immortalized in Scottish ballads and military histories for its dramatic brevity and impact.
1745
Sir John Cope
defeated
Jacobite
Prince Charles Edward Stuart
1776day.year
Part of New York City is burned shortly after being occupied by British forces.
After British forces occupied New York City in September 1776, a fire swept through Lower Manhattan, causing widespread destruction.
In the wake of the Battle of Long Island, British troops under General Howe entered New York City in mid-September 1776. On September 21, a massive fire broke out in the occupied city, destroying homes, warehouses, and public buildings in Lower Manhattan. Controversy surrounds the blaze, with both British and American accounts accusing the other side of arson. The inferno consumed some 500 structures, leaving hundreds of civilians homeless and crippling local commerce. Despite the destruction, the British used New York as a key strategic base for the remainder of the Revolutionary War. The event underscored the human cost of war and fueled American resentment toward occupying forces. The remains of burned districts were later rebuilt, shaping the city's future urban landscape.
1776
New York City
burned
1780day.year
American Revolutionary War: Benedict Arnold gives the British the plans to West Point.
On September 21, 1780, American General Benedict Arnold met with the British, providing them with detailed plans to capture West Point.
Benedict Arnold, once a celebrated hero of the American Revolution, grew disillusioned with Continental Congress and his own treatment. In early 1780, he began secret negotiations with British Major John Andre to betray the strategic fort at West Point. On September 21, Arnold guided Andre aboard the HMS Vulture in the Hudson River, handing over maps and defensive documents. His treason threatened to hand control of West Point to British forces, which would have split the colonies in two. By late September, Andre was captured with incriminating papers, and Arnold's plot was uncovered. Arnold escaped to New York City, where he received a commission in the British Army, leaving his American reputation in ruins. The incident remains one of the most infamous acts of betrayal in U.S. history, highlighting the fragile loyalties of war.
1780
American Revolutionary War
Benedict Arnold
1860day.year
Second Opium War: An Anglo-French force defeats Chinese troops at the Battle of Palikao.
At the Battle of Palikao, Anglo-French forces decisively defeat Qing troops, opening the way for further concessions in China.
Fought on September 21, 1860, the Battle of Palikao saw combined British and French armies clash with Qing dynasty forces. Under General Cousin-Montauban and Lord Elgin, the allies used superior artillery to breach Chinese defenses. The defeat opened the route to Beijing and pressured the imperial court into negotiations. This engagement marked a turning point in the Second Opium War, demonstrating Western military dominance. The subsequent treaties expanded foreign trade rights and diplomatic privileges in China.
1860
Second Opium War
Battle of Palikao
1862day.year
Taiping Rebellion: The Ever Victorious Army defeats Taiping forces at the Battle of Cixi.
The Ever Victorious Army led by Western officers defeats Taiping rebels at Cixi, securing a key Qing victory.
On September 21, 1862, the Qing government’s Ever Victorious Army routed Taiping Rebel forces at Cixi. Commanded by foreign officers such as Frederick Townsend Ward and later Charles Gordon, this unit combined Western military tactics with local troops. The victory halted the southward advance of the Taiping Heavenly Kingdom and bolstered Qing morale. It showcased the growing influence of foreign military advisors in China’s internal conflicts. Although the rebellion continued until 1864, the setback at Cixi weakened the Taiping movement significantly.
1862
Taiping Rebellion
Ever Victorious Army
Battle of Cixi
1896day.year
Anglo-Egyptian conquest of Sudan: British forces under the command of Horatio Kitchener take Dongola.
British forces led by Horatio Kitchener capture Dongola, advancing the Anglo-Egyptian conquest of Sudan.
The assault on Dongola on September 21, 1896, was a pivotal moment in the Anglo-Egyptian campaign to reconquer Sudan. Under Lord Kitchener’s leadership, British and Egyptian troops employed modern artillery and disciplined infantry tactics. They overwhelmed Mahdist defenders and secured the town as a strategic foothold. This victory opened the Nile corridor toward Khartoum and marked the beginning of the end for the Mahdist State. Established in 1885, the Mahdist regime would fall two years later at the Battle of Omdurman, solidifying British-Egyptian control over Sudan.
1896
Anglo-Egyptian conquest of Sudan
Horatio Kitchener
Dongola
1942day.year
The Holocaust in Ukraine: On the Jewish holiday of Yom Kippur, Nazis send over 1,000 Jews of Pidhaitsi to Bełżec extermination camp.
On Yom Kippur 1942, more than 1,000 Jews from Pidhaitsi were deported to the Bełżec extermination camp.
On September 21, 1942, German forces in occupied Ukraine carried out a brutal roundup of the Jewish community in Pidhaitsi.
The operation coincided with Yom Kippur, magnifying the cruelty of the deportations.
Over 1,000 men, women, and children were forced onto trains bound for the Bełżec extermination camp, where most were immediately murdered.
Bełżec was one of the primary sites of Operation Reinhard, the Nazi plan to exterminate the Jews of Eastern Europe.
The massacre at Pidhaitsi exemplifies the systematic and industrialized nature of the Holocaust.
Today, memorials and historical research ensure that the victims' stories are not forgotten.
1942
The Holocaust in Ukraine
Yom Kippur
Pidhaitsi
Bełżec extermination camp
1942day.year
The Holocaust in Ukraine: In Dunaivtsi, Ukraine, Nazis murder 2,588 Jews.
In Dunaivtsi, Ukraine, Nazi forces executed 2,588 Jewish residents in a single day.
On September 21, 1942, in the town of Dunaivtsi, German troops and local collaborators carried out a mass shooting of the Jewish population.
A total of 2,588 men, women, and children were forced to march to a nearby ravine and shot on the spot.
This atrocity was part of the wider Holocaust campaign in Ukraine, driven by Nazi ideology and anti-Semitism.
Survivors' accounts describe the terror and chaos as families were torn apart without warning.
The site of the massacre now serves as a somber memorial, reminding visitors of the horrors faced by the Jewish community.
Historians continue to document testimonies and preserve evidence of the Dunaivtsi massacre.
Dunaivtsi
1942day.year
The Holocaust in Poland: At the end of Yom Kippur, Germans order Jews to permanently move from Konstantynów to Biała Podlaska.
After Yom Kippur 1942, German authorities ordered the Jews of Konstantynów to relocate permanently to Biała Podlaska.
At the close of Yom Kippur on September 21, 1942, the Nazi administration in occupied Poland mandated the forced relocation of the Jewish residents of Konstantynów.
All remaining individuals were rounded up and sent to the nearby transit point of Biała Podlaska under armed escort.
This move was part of a broader strategy of ghetto liquidation and concentration of Jewish communities.
Life in Biała Podlaska was harsh, with overcrowding, disease, and limited resources compounding their suffering.
Many of those relocated would later face deportation to extermination camps.
The forced transfer illustrates the calculated progression of Holocaust policies across occupied territories.
The Holocaust in Poland
Biała Podlaska
2012day.year
Three Egyptian militants open fire on a group of Israeli soldiers in a southern Israel cross-border attack.
Egyptian militants carried out a cross-border shooting against Israeli soldiers in southern Israel in 2012.
On September 21, 2012, three Egyptian militants opened fire on Israeli soldiers near Israel's southern border. The cross-border attack took place in the Sinai Peninsula, where insurgents had escalated violence. Israeli forces returned fire and pursued the attackers back across the border. The incident underscored the fragile security situation between Israel and Egypt following the Arab Spring. It prompted joint discussions on border patrol and counterterrorism between the two nations. No Israeli soldiers were reported killed, but the event heightened regional tensions.
2012
Egyptian
Israeli soldiers
southern Israel cross-border attack