In the mid-1870s and 1880s Giquel became increasingly involved in international diplomacy . He first served as an adviser during the " Taiwan crisis " , a diplomatic clash between Japan and China in 1874 culminating with Japan 's invasion of the island . In 1881 he helped Tseng Chi-tse peacefully conclude the " III crisis " between China and Russia . Giquel spent his last years ( 1883 – 1885 ) struggling to help end the Sino-French War , which had broken out due to conflicting Sino-French claims to Indochina . Among the traumatic events of that period , certainly for Prosper Giquel , was the August 1884 destruction by the French Navy of the Fuzhou Dockyard , the principal accomplishment of his entire career in China , in the Battle of Fuzhou
Taiwan crisis
Mudan incident
Prosper Giquel