18 September 1781

Five letters containing anthrax spores were mailed to various media outlets in the United States.

Aeroflot Flight 213 crashed into a mountain near Chersky Airport, killing 32 people.

An aircraft crashed near Ndola in Northern Rhodesia, resulting in the deaths of 16 people, including United Nations secretary-general Dag Hammarskjöld.

Korean War: The Korean People's Army retreated from the Battle of the Pusan Perimeter after six weeks of fighting, marking the farthest that the KPA would advance in the war.

The Australian cricket team's Invincibles tour of England concluded; they had played 34 matches, including five Tests, without defeat.

World War I: The Central Powers' defeat at the Battle of Dobro Pole played a role in the Bulgarian withdrawal from the war and led to the subsequent liberation of Vardar Macedonia.

The Blackpool Illuminations (example pictured) in the English seaside town of Blackpool were switched on for the first time.

The Indianola hurricane dissipated over Mississippi after killing around eight hundred people in Texas.

Panic of 1873: The American bank Jay Cooke & Company declared bankruptcy, setting off a chain reaction of bank failures.

Nathaniel P. Langford of the Washburn–Langford–Doane Expedition first observed a geyser in the Wyoming Territory erupting at regular intervals, naming it Old Faithful (video featured).

The New York Times, the largest metropolitan newspaper in the United States, was founded.

The United States Congress passed the Fugitive Slave Act, decreeing that all escaped slaves be brought back to their masters.

Byzantine–Seljuk wars: Byzantine forces defeated their Seljuk opponents in the flanks of the nocturnal Battle of Kapetron, but learned of their Georgian allies' defeat in the centre the next morning.

Constantine the Great decisively defeated Licinius in the Battle of Chrysopolis, establishing Constantine's sole control over the Roman Empire and ending the Tetrarchy.

Cannabis is legalized in South Africa, through a ruling of the Constitutional Court.

Toy retail chain Toys "R" Us files for bankruptcy protection in the United States and Canada.

The 2016 Uri attack in Jammu and Kashmir, India by terrorist group Jaish-e-Mohammed results in the deaths of nineteen Indian Army soldiers and all four attackers.

Scotland votes against independence from the United Kingdom, by 55% to 45%.

A VIA Rail train crashes into a double-decker bus at a train station in Ottawa, Canada, killing six people and injuring 35 others.

Philippe Croizon becomes the first quadruple amputee to swim across the English Channel.

After 72 years on radio and television, CBS Television broadcasts the final episode of Guiding Light, the longest-running soap opera in American history.

Buddhist monks join anti-government protesters in Myanmar, starting what some call the Saffron Revolution.

The CW Television Network debuts in the US, following the merger of UPN and The WB.

First mailing of anthrax letters from Trenton, New Jersey in the 2001 anthrax attacks.