Sion Longley Wenban (19 March 1848, Cincinnati - 20 April 1897, Munich) was an American landscape painter and graphic artist who emigrated to Germany.
He originally worked with his father but, at the age of fifteen, became a retoucher[1] in the photography studios of James F. Ryder (1826-1904), where his uncle, the painter Thomas Stevenson, was already employed.
Upon returning to Cleveland, he made friends with the painter Otto Henry Bacher, who helped him to learn etching.
Another American painter studying there, Frank Duveneck, from Kentucky, also played a significant role.
[1] That same year, he married Bertha von Langenmantel, the daughter of a royal building inspector.