September 22

Samogitian forces defeat the Livonian Brothers of the Sword at the Battle of Saule.

Pagan Samogitian warriors decisively defeated the crusading Livonian Brothers of the Sword at the Battle of Saule in present-day Lithuania, a defeat so severe that the surviving remnants of the military order were absorbed into the larger Teutonic Order shortly afterward. The battle marked a significant early setback for northern European Christian crusading efforts against Baltic pagan peoples.

The Treaty of Basel concludes the Swabian War between the Swiss Confederacy and the Holy Roman Empire.

The Treaty of Basel formally concluded the Swabian War between the Swiss Confederacy and the Holy Roman Empire, a brief but decisive conflict sparked by disputes over territorial rights and tribute payments. The settlement effectively recognized Swiss independence from imperial authority in all but name, decades before formal international recognition of Swiss sovereignty followed at the end of the Thirty Years' War.

Spanish forces fight their way past an English and Dutch ambush at the Battle of Zutphen.

Spanish troops resupplying the besieged garrison at Zutphen fought their way past an ambush laid by combined English and Dutch forces, a battle notable for the mortal wounding of English poet and soldier Sir Philip Sidney, who died from his injuries weeks later.

Eight people are hanged in Salem, Massachusetts, the last executions of the Salem witch trials.

The last eight people convicted in the notorious Salem witch trials were hanged, bringing to a close a period of hysteria that had resulted in the deaths of twenty people, a chapter in colonial American history now widely regarded as a profound miscarriage of justice.

George III and Charlotte of Mecklenburg-Strelitz are crowned King and Queen of Great Britain.

The young King George III and his new bride, Princess Charlotte of Mecklenburg-Strelitz, were formally crowned in a lavish coronation ceremony at Westminster Abbey, beginning a reign that would prove to be one of the longest in British history to that point.

American revolutionary Nathan Hale is executed by British forces for espionage.

Convicted of espionage after volunteering to gather intelligence behind British lines in New York, the young American soldier Nathan Hale was executed by hanging without a formal trial, reportedly declaring his regret at having only one life to give for his country. His words, though possibly embellished by later retellings, made him a celebrated martyr of the American Revolution.

Abraham Lincoln issues the preliminary Emancipation Proclamation.

President Abraham Lincoln issued a preliminary version of the Emancipation Proclamation following the Union's tactical victory at Antietam, warning that he would formally free enslaved people in Confederate-held territory if the rebellion did not end by the start of the new year.

Queen Victoria becomes the longest-reigning British monarch to that point, surpassing King George III.

Queen Victoria surpassed her grandfather King George III's tenure to become the longest-reigning monarch in British history to that date, a remarkable milestone during a reign that had already witnessed enormous industrial, social, and imperial transformation. Rather than a public celebration, Victoria, still in mourning for her husband Prince Albert decades earlier, marked the occasion privately and modestly.

German and Soviet forces hold a joint military parade in Brest-Litovsk following the invasion of Poland.

German and Soviet military forces held a joint victory parade in the Polish city of Brest-Litovsk following their coordinated invasion and partition of Poland, a striking public display of cooperation between the two totalitarian powers before their alliance later collapsed into war.

Iraq invades Iran, sparking the eight-year Iran-Iraq War.

Iraqi forces under Saddam Hussein launched a surprise invasion of neighboring Iran, seeking to exploit the chaos following Iran's Islamic Revolution and settle longstanding border and territorial disputes. The resulting eight-year war produced enormous casualties on both sides, including extensive use of chemical weapons, without ultimately producing a decisive military outcome or significant border changes.