July 17

Fourth Crusade forces assault Constantinople, prompting Byzantine Emperor Alexios III to flee into exile.

Knights of the Fourth Crusade, diverted from their original goal of reaching the Holy Land, launched an assault on Constantinople to restore a deposed claimant to the Byzantine throne. Facing the attack, Emperor Alexios III fled the city, though the crusaders' intervention ultimately led to the catastrophic sack of Constantinople the following year.

Charles VII is crowned King of France at Reims Cathedral, a triumph achieved largely through Joan of Arc's military campaign.

With Joan of Arc at his side following her string of military successes against the English, the Dauphin Charles was formally crowned King Charles VII of France in the traditional coronation city of Reims. The ceremony was a major propaganda and morale victory for the French cause during the Hundred Years' War.

The Battle of Castillon concludes the Hundred Years' War with a decisive French victory over English forces in Gascony.

The last major engagement of the Hundred Years' War saw French forces, employing early field artillery to devastating effect, decisively defeat an English army near Castillon in Gascony. The battle effectively ended English territorial ambitions on the European mainland, concluding well over a century of intermittent Anglo-French conflict.

King George I's barge procession on the Thames features the premiere of George Frideric Handel's "Water Music."

During a royal barge procession along the Thames intended to please King George I, an orchestra performed Handel's newly composed suite for the first time, reportedly delighting the king so much that he requested it be repeated multiple times during the journey. The suite remains one of Handel's most celebrated and frequently performed orchestral works.

Spain formally cedes Florida to the United States.

Under the terms of the Adams-Onis Treaty negotiated with the United States, Spain relinquished its claim to Florida, a territory it had struggled to defend and administer effectively amid growing American pressure. The cession resolved long-standing border disputes and extended U.S. territory along the Gulf Coast.

Former Tsar Nicholas II and his family are executed by Bolshevik forces at the Ipatiev House in Yekaterinburg.

Amid the chaos of the Russian Civil War, Bolshevik guards executed the deposed Tsar Nicholas II, his wife, their five children, and several attendants in the basement of a house in the Ural Mountains, fearing the royal family's rescue by advancing anti-Bolshevik forces. The killings ended three centuries of Romanov rule in brutal and controversial fashion.

A military uprising against Spain's Popular Front government begins, marking the start of the Spanish Civil War.

A rebellion by right-wing military officers, including General Francisco Franco, against Spain's democratically elected leftist government erupted into full civil war, drawing in international volunteers and foreign intervention from Germany, Italy, and the Soviet Union. The conflict, marked by extreme brutality, ended in 1939 with Franco's establishment of a decades-long dictatorship.

American and Soviet spacecraft dock in orbit during the Apollo-Soyuz Test Project, a symbolic moment of Cold War cooperation.

American astronauts and Soviet cosmonauts successfully linked their respective spacecraft in Earth orbit, exchanging handshakes and gifts through the connecting hatch in a highly symbolic gesture of Cold War cooperation. The Apollo-Soyuz Test Project remains a landmark moment of scientific collaboration amid ongoing geopolitical rivalry.

TWA Flight 800 explodes and crashes off Long Island, New York, killing all 230 people aboard.

A Boeing 747 bound for Paris exploded shortly after takeoff from New York, killing all 230 people aboard. Investigators eventually attributed the disaster to a spark igniting fuel vapors in a nearly empty center fuel tank, a finding that led to significant changes in aircraft fuel tank design and safety regulations.

Malaysia Airlines Flight 17 is shot down over eastern Ukraine, killing all 298 people aboard.

A Malaysia Airlines passenger jet flying from Amsterdam to Kuala Lumpur was struck by a surface-to-air missile over territory controlled by Russian-backed separatists in eastern Ukraine, killing everyone aboard. International investigators concluded the missile was fired from a Russian-supplied system, further inflaming the conflict in the region.