A German career diplomat who first served in China during the 1880s, Clemens von Ketteler returned in 1899 as plenipotentiary at Peking (Beijing). He became involved in rising tensions there, ordering German embassy guards to hunt down Boxers who had burned church buildings. The violence escalated, with Ketteler attacking a Chinese civilian and shooting a boy, provoking an armed riot. On 20 June 1900, Ketteler and his armed guard became involved in a firefight with a Manchu unit on their way to the Chinese foreign ministry, during which Ketteler was shot by the Manchu captain En Hai. En Hai was subsequently captured and executed.
The Ketteler memorial in Beijing was built after the Boxer rebellion was put down. It was completed on 8 January 1903, at the site where Ketteler was killed. After the First World War, the memorial ceased to function as such and was moved to the present-day Zhongshan Park as "The Victory of Justice Gate" In 1953, it was renamed "The Protection of Peace Gate".
Dedication of Memorial Gateway Arch (Ketteler Memorial) in Peking, China, black-and-white photograph, 1903, unknown photographer; source: Digital Commonwealth, http://ark.digitalcommonwealth.org/ark:/50959/n8710222h Attribution Non-Commercial No Derivatives 3.0 Unported .