14 September 1947

Drone attacks on major processing facilities at Abqaiq and Khurais forced Saudi Arabia to cut more than half of its oil production.

Physicists of the LIGO and Virgo projects first observed gravitational waves, the existence of which was predicted by Henri Poincaré in 1905.

Late-2000s financial crisis: The Northern Rock bank received a liquidity support facility from the Bank of England, sparking a bank run—the United Kingdom's first in 150 years.

President Kumba Ialá (pictured) of Guinea-Bissau was deposed in a bloodless military coup.

The Constitutional Court of Bosnia and Herzegovina declared the breakaway Croatian Republic of Herzeg-Bosnia to be unconstitutional.

Typhoon Sarah dissipated after causing extensive damage along an erratic path across the Western Pacific, killing 71 in Taiwan, the Philippines, and the Gotō Islands.

Afghan president Nur Muhammad Taraki (pictured) was overthrown and later killed on the orders of Hafizullah Amin, who succeeded him.

At a conference held in Baghdad, the governments of Iran, Iraq, Kuwait, Saudi Arabia, and Venezuela founded OPEC to help coordinate their petroleum policies and influence global oil prices.

World War II: Nazi forces began a mass extermination campaign against the civilian residents of around 20 villages on the Greek island of Crete, eventually killing more than 500 men.

Hungarian forces massacred at least 150 ethnic Romanians in Ip, Transylvania, following rumors that Romanians were responsible for the deaths of two soldiers.

HMAS AE1 (pictured), the Royal Australian Navy's first submarine, was lost at sea; its wreck was not found until 2017.

Theodore Roosevelt became President of the United States at age 42, the youngest person ever to do so, eight days after William McKinley was fatally wounded in Buffalo, New York.

American Civil War: The Little Rock campaign ended with the Union Army capturing Little Rock, Arkansas.

Under the terms of the Calendar (New Style) Act 1750, the British Empire adopted the Gregorian calendar, skipping 11 days of the month.

António Manoel de Vilhena, Grand Master of the Knights Hospitaller, laid the first stone of Fort Manoel in Malta.

Viking activity in the British Isles: A coalition of native Irish, led by Niall Glúndub, failed in their attempt to drive the Vikings of the Uí Ímair from Ireland.

Death of Queen Elizabeth II: The Queen's coffin is taken from Buckingham Palace, placed on a gun carriage of The King's Troop Royal Horse Artillery and moved in a procession to Westminster Hall for her lying in state over the next four days with the queue of mourners stretching for miles along the River Thames.

Yemen's Houthi rebels claim responsibility for an attack on Saudi Arabian oil facilities.

The first observation of gravitational waves is made, announced by the LIGO and Virgo collaborations on 11 February 2016.

Aeroflot Flight 821, a Boeing 737-500, crashes into a section of the Trans-Siberian Railway while on approach to Perm International Airport, in Perm, Russia, killing all 88 people on board.

Prelude to the 2008 financial crisis: Northern Rock bank experiences the first bank run in the United Kingdom in 150 years.

In a referendum, Estonia approves joining the European Union.

Bissau-Guinean President Kumba Ialá is ousted from power in a bloodless military coup led by General Veríssimo Correia Seabra.

Total Linhas Aéreas Flight 5561 crashes near Paranapanema, Brazil, killing both pilots on board.