February 21

Imam Ahmad of Adal had overrun most of the Christian highlands since 1529. Emperor Gelawdewos, with the last Portuguese musketeers of Cristóvão da Gama’s force, killed him in battle and the invasion collapsed.

The Dialogue Concerning the Two Chief World Systems was written in Italian, for everyone, and gave the Pope’s own argument to a character named Simplicio. Urban VIII took it personally, and sales were stopped that summer.

To win a bet for ironmaster Samuel Homfray, Trevithick’s engine hauled 10 tons of iron and about 70 men nearly ten miles down the tramroad from Merthyr Tydfil to Abercynon. It was the first railway journey by a steam locomotive, and the engine’s weight broke the cast-iron plates.

A few men camped on the beach fifteen miles south of the fort and boiled seawater in kettles day and night, making salt for the journey home. The stone cairn of their furnace is still there.

The first Native American newspaper, printed in English and in Sequoyah’s syllabary at the Cherokee capital of New Echota, with type cast in Boston. Its editor was Elias Boudinot, and it opposed the state of Georgia’s push to remove the Cherokee from their land.

The longest battle of the war, fought in a few square kilometres around the forts of Verdun. France rotated most of its army through it along a single road, the Voie Sacrée. The two sides lost about 700,000 men killed, wounded and missing, some 300,000 of them dead, and the line ended close to…

He was shot as he began to speak at the Audubon Ballroom, aged 39, a year after breaking with the Nation of Islam. Three members of the Nation were convicted; in 2021 the convictions of two of them, Muhammad Aziz and Khalil Islam, were thrown out after a review found the evidence had been withheld.

In a house in a Paris suburb, Nixon’s national security adviser met the Politburo member who would negotiate for Hanoi for the next three years. Thọ’s message never changed: all American troops out, and Thiệu gone.

Hours after landing in Beijing, Richard Nixon was taken to meet Mao Zedong. By playing China against the Soviet Union, Washington turned the Cold War into a three-cornered game.

The royal government and the Pathet Lao signed the Vientiane Agreement, setting up a coalition. The last American bombing in Laos came in April. In 1975 the Pathet Lao took power without a battle.

A physician who had treated pneumonia patients in Guangdong stayed one night on the ninth floor of a Hong Kong hotel. Guests who were there that night seeded outbreaks in Hong Kong, Vietnam, Singapore and Toronto.