September 4

Germanic general Odoacer deposes Romulus Augustulus and proclaims himself King of Italy, traditionally marking the end of the Western Roman Empire.

The Germanic military leader Odoacer, commanding a mixed force of Roman auxiliary troops, deposed the teenage emperor Romulus Augustulus and sent him into comfortable retirement rather than executing him. Odoacer then styled himself King of Italy rather than claiming the imperial title, an event historians traditionally use to mark the symbolic end of the Western Roman Empire, though Byzantine rule continued in the east.

Li Shimin, later Emperor Taizong, secures control of the Tang dynasty following a violent succession struggle.

Li Shimin eliminated his brothers in a violent succession struggle known as the Xuanwu Gate Incident before forcing his father to abdicate in his favor, becoming Emperor Taizong of the newly established Tang dynasty. Despite the bloody circumstances of his rise, Taizong's subsequent reign is regarded as one of the most successful and culturally flourishing periods in Chinese imperial history.

Sienese Ghibelline forces defeat Florentine Guelphs at the Battle of Montaperti.

Ghibelline forces from Siena, aided by exiled Florentine Ghibellines and German mercenary cavalry, inflicted a devastating defeat on the rival Guelph army from Florence near the Arbia River. The battle, one of the bloodiest in medieval Italian history, temporarily shifted political power in Tuscany, though the Guelphs regained dominance in Florence within less than a decade.

The Treaty of Alcacovas is signed between the Catholic Monarchs of Castile and Aragon and Portugal, settling territorial disputes.

Negotiated to resolve a war of succession over the Castilian throne, the treaty settled competing territorial claims between Portugal and the combined Spanish kingdoms, notably granting Portugal exclusive rights to territories south of the Canary Islands, including along the West African coast. The agreement significantly shaped the subsequent competition between the two Iberian powers during the early age of European exploration.

Irish earls flee to mainland Europe in the Flight of the Earls, ending Gaelic aristocratic resistance to English rule.

Facing mounting pressure from English colonial authority following the collapse of a major Gaelic rebellion, the last independent Gaelic Irish earls sailed into exile on the European continent, effectively ending centuries of Gaelic aristocratic power in Ulster. Their departure opened the way for the large-scale English and Scottish colonization of Ulster that followed in subsequent years.

Spanish settlers found the settlement that becomes Los Angeles, naming it El Pueblo de Nuestra Senora la Reina de los Angeles.

A group of Spanish colonial settlers, including families of mixed Spanish, Indigenous, and African descent, founded a small farming pueblo near the Los Angeles River under orders from the Spanish governor of California. The settlement grew slowly over the following decades before eventually becoming one of the largest and most influential cities in the United States.

Emperor Napoleon III of France is deposed and the Third French Republic is declared.

Following Napoleon III's humiliating capture at the Battle of Sedan during the Franco-Prussian War, crowds in Paris rose up and proclaimed the end of the Second French Empire, establishing the Third Republic in its place. The new republican government continued the war against Prussia, though Paris itself would soon face a lengthy and difficult siege.

Pearl Street Station in New York City becomes the first power plant to supply electricity to paying customers.

Thomas Edison's Pearl Street Station in lower Manhattan began supplying direct current electricity to a small number of paying customers in the surrounding financial district, marking a foundational moment in the commercialization of electric power. The station's success helped launch the broader electrification of American cities in the following decades.

Apache leader Geronimo surrenders to General Nelson Miles, ending nearly three decades of armed resistance.

After leading Apache resistance fighters through decades of conflict with American and Mexican forces across the Southwest, Geronimo formally surrendered to General Nelson Miles in Arizona, marking the end of major armed Native American resistance in the region. Geronimo spent the remainder of his life as a prisoner of war, eventually becoming something of a celebrity figure before his death in 1909.

Google is founded by Stanford PhD students Larry Page and Sergey Brin.

Working from a garage in Menlo Park, California, Larry Page and Sergey Brin formally incorporated their search engine company, which had grown out of a research project exploring how to rank web pages by analyzing the links between them. Google went on to become one of the most valuable and influential technology companies in the world, fundamentally reshaping how people access information online.