1 March 1896, the hills of Adwa in Tigray. Emperor Menelik II and Empress Taytu have gathered an army Europe was told not to imagine, perhaps 100,000 strong, many with modern rifles. General Baratieri marches up from the Italian colony of Eritrea with about 17,000 men because Rome wants a victory. By afternoon the invasion is a wreck.
Why then
The Treaty of Wuchale, signed in 1889, has two readings of one article. The Italian text makes Ethiopia a protectorate; the Amharic text does not. A stalled campaign looks like weakness to the government in Rome, which presses Baratieri to attack a far larger army.
What they wanted
Italy is after a Horn of Africa to match the other empires, and a battle that makes the protectorate true. Menelik wants his empire recognised as a sovereign state. Taytu, who saw through the treaty early, means to drive the Italians off the highlands.
What changed
Some 6,000 Italians die, the worst defeat a European army suffers in Africa in that century. The Treaty of Addis Ababa that October recognises Ethiopia's independence, and Italy's prime minister falls. When Italy returns in 1935, it comes for revenge.
Still argued
Raymond Jonas argues that Europe spent decades explaining the victory away, as numbers or ground rather than Menelik's rifles and diplomacy, which is part of why it still matters.