Spreads across the world

Tang alchemists wrote down the first gunpowder mixtures in the 9th century, and Song, Jin and Yuan armies made them into bombs, fire lances and the first guns. Guns reached Europe, the Islamic world, Korea and Đại Việt in the 14th century, by ways seldom recorded, and Ottoman and Portuguese matchlocks reached India and Japan in the 16th.

Places reached

23 places

Began

Began at Tang China (Chang'an)

Strands: Gunpowder and bombs, Guns and cannon, Matchlock guns

Printing from reusable type began in East Asia: Bi Sheng made clay type in the 1040s, Wang Zhen wooden type about 1298, and Korea printed with cast metal type by 1377. About 1450 Gutenberg put metal type and a press together at Mainz, and German printers and their pupils took the craft to more than 200 European towns by 1500.

Places reached

41 places

Began

Began at Jingde

Strands: Movable type in East Asia, Gutenberg's press in Europe

A pandemic of plague, caused by the bacterium Yersinia pestis, that swept western Asia, North Africa and Europe from 1346 to 1353 and killed perhaps a third or more of their people. Ancient DNA traces its strain to an outbreak in Central Asia in 1338–1339. Plague returned in waves for four more centuries.

Places reached

45 places

Began

Began at Kara-Djigach

Strands: First wave, Pestis secunda, Italian plague of 1629–1631, Naples plague, Great Plague of London, Great Plague of Marseille, Russian plague of 1770–1772

After 1492 ships, armies and settlers carried crops and animals between the Americas and the Old World. Maize, potatoes, sweet potatoes and chili spread to fields and kitchens from Ireland to China and Vietnam, while horses changed war and travel in the Americas and sugar cane grew on plantations worked by enslaved Africans.

Places reached

35 places

Began

Began at Gibara

Strands: Maize, Potato, Chili pepper, Sweet potato, Horse, Sugar cane