"Boxers" was the English name given to participants in the anti-imperialist, anti-Western uprising in China between 1899 and 1901. The movement's actual name was "Militia United in Righteousness" (Yihetuan). The uprising was put down by Western forces, and the Boxer Protocol of 1901 imposed severe reparations on China.
A Chinese "Boxer", black-and-white photograph, 1900, unknown photographer; source: National Archives (USA), public domain.