The Chatti were a Germanic people who originally inhabited the upper Wesser River region, in northwestern Germany, around 70 BC, being part of the Suevi confederacy of tribes. In 9 AD, they made an alliance with the Cheruscan, under Arminius, to fight and stop the Roman legions, under Varus, invading their land; they defeated the Romans, under Publius Qunctilius Varus, in the Battle of the Teutoburg Forest, during the reign of emperor Augustus. In 162 AD, along with the Chauci, they crossed the border and poured into Roman territory, attacking a Roman legion outpost, but they were thrown back after three years of ferocious war.  By 5th century AD, the Chatti had become part of the Franks, who invaded the Gauls (France) at the Fall of the Roman Empire.

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