1899 – June 1900 · Shandong and Zhili provinces, North China Theater

Amid drought, famine, and resentment at foreign missionaries and railways, the secret society of the 'Boxers' — the Righteous and Harmonious Fists, who believed martial rituals made them invulnerable to bullets — spread across the North China plain, attacking Christian converts, missionaries, churches, railways, and telegraph lines. Thousands of Chinese Christians were killed as the movement swelled toward Peking.

June 10–26, 1900 · Railway between Tientsin and Peking Theater

As the Boxers cut the Peking legations off from the coast, Admiral Seymour led a scratch force of some 2,000 allied sailors and marines up the railway to relieve them. Boxers and, increasingly, regular Qing soldiers tore up the track and attacked the column at Langfang and elsewhere; unable to break through, Seymour's force was itself surrounded and had to fight its way back to Tientsin with heavy losses.

June 17, 1900 · Mouth of the Hai River Theater

To secure their line of communication from the sea, the allied navies demanded and then stormed the Qing forts guarding the mouth of the Hai River at Taku, capturing them after a night bombardment and assault. The attack on Chinese soil helped push the Qing court into a formal declaration of war.

June 20 – August 14, 1900 · Legation Quarter, Peking Theater

For fifty-five days, some 900 foreign soldiers and civilians and around 3,000 Chinese Christians barricaded themselves in the Legation Quarter of Peking, defending an improvised perimeter against Boxers and Qing soldiers with rifles, one antique cannon dubbed 'the International,' and desperate improvisation. The German minister had already been murdered in the streets. Food ran short and the defenders were nearly overwhelmed several times before relief arrived on August 14.

June – August 1900 · Peking Theater

Separate from the legations, thousands of Chinese Catholic converts sheltered in the Beitang cathedral compound, defended by only a few dozen French and Italian marines under Bishop Favier. Through the same 55 days they endured starvation, mines exploded beneath them, and constant assault, suffering heavy losses among the refugees before they too were relieved.

July 13–14, 1900 · Tientsin (Tianjin) Theater

The allied armies gathering at Tientsin stormed the walled native city after fierce fighting, in which the future US president Herbert Hoover, a young mining engineer trapped in the foreign settlement, helped organise the defences. The capable Qing general Nie Shicheng was killed. With Tientsin secured, the allies had a firm base for the march on Peking.

August 5–6, 1900 · Between Tientsin and Peking Theater

The international relief column of some 20,000 — Japanese, Russian, British, American, French, and others — pushed up the Hai River toward Peking in blistering August heat, brushing aside Qing resistance at Beicang and Yangcun. Rivalry and mistrust divided the allied contingents even as they advanced together.

August 14, 1900 · Peking Theater

On August 14 the relief army fought its way through the gates and walls of Peking, each national contingent racing to be first to the legations. British and American troops reached the besieged quarter that afternoon, ending the 55-day siege; the Beitang was relieved days later. The Empress Dowager and the court fled the city in disguise.

July – October 1900 · Manchuria (northeast China) Theater

Using the Boxer attacks on its railways as a pretext, Russia poured over 100,000 troops into Manchuria and occupied the whole region, crushing Qing and Boxer resistance. The campaign was marked by atrocities, most infamously the massacre and drowning of thousands of Chinese civilians across the Amur at Blagoveshchensk.

August 1900 – 1901 · Peking and North China Theater

After the relief, the allied armies plundered Peking and the imperial palaces and mounted punitive expeditions across the countryside to hunt Boxers and punish villages, often indiscriminately. The German force in particular, arriving late under Field Marshal von Waldersee, carried out reprisals in the spirit of the Kaiser's notorious 'Hun speech.' Widespread looting, executions, and abuses fell on the Chinese population.