August 21st, 1451

Born on August 21st, 1451

Age in days, weeks and months
Wow, over 209,000 days old!

Why not celebrate an alternative birthday? In 11 days, exactly on August 6th, 2026, people who were born on August 21st, 1451 will be 210,000 days old!

... in seconds, minutes and hours

What happened on August 21st?

August 21st, 2007

BioShock was released in North America, becoming a critical success and a demonstration of video games as an art form.

August 21st, 2015

Passengers on a Thalys train from Amsterdam to Paris confronted and subdued an attacker who attempted a mass shooting.

August 21st, 2013

Syrian civil war: Areas controlled by the Syrian opposition in Ghouta, Damascus, were attacked by rockets (launcher pictured) containing sarin, killing at least 281 people.

August 21st, 1986

A limnic eruption of Lake Nyos in Cameroon released a cloud of carbon dioxide, suffocating 1,746 people and 3,500 livestock.

August 21st, 1963

South Vietnamese special forces loyal to Ngô Đình Nhu, the brother of President Ngô Đình Diệm, raided and vandalised Buddhist pagodas (one pictured) across the country, arresting thousands and leaving hundreds dead.

August 21st, 1945

American physicist Harry Daghlian accidentally dropped a tungsten carbide brick onto a plutonium bomb core, exposing himself to neutron radiation and later becoming the first Manhattan Project fatality due to a criticality accident.

August 21st, 1944

World War II: A combined Canadian–Polish force captured the town of Falaise, France, in the final offensive of the Battle of Normandy.

August 21st, 1942

World War II: The Imperial Japanese Army lost the Battle of the Tenaru, the first of its three major land offensives during the Guadalcanal campaign.

August 21st, 1911

Leonardo da Vinci's Mona Lisa (pictured) was stolen from the Louvre by museum employee Vincenzo Peruggia and was not recovered until two years later.

August 21st, 1858

The first of seven debates between Abraham Lincoln and Stephen A. Douglas (both pictured), candidates for an Illinois seat in the U.S. Senate, was held in Ottawa, Illinois.

August 21st, 1808

Peninsular War: British and Portuguese forces put an end to the first French invasion of Portugal at the Battle of Vimeiro.

August 21st, 1789

The national colours of Italy first appeared on a tricolour cockade in Genoa.

August 21st, 1717

Austro-Turkish War: Austrian troops under Prince Eugene of Savoy captured the strategically important city of Belgrade from the Ottoman Empire.

August 21st, 1716

Seventh Ottoman–Venetian War: Ottoman forces suddenly abandoned their siege of Corfu, allowing the Republic of Venice to preserve its rule over the Ionian Islands.

August 21st, 1689

Jacobite clans clashed with a regiment of Covenanters in the streets of Dunkeld, Scotland.

Public holidays on August 21st

Fixed holidays (Christian Feast Day) which are celebrated on August 21st.

Date as a Roman numeral / digit

Leap year

No: With 365 days 1451 is a normal year and no leap year.

Calendar
August 1451