Gustav Keller founded his namesake in 1856 by Gustave Keller who began in jewelry and silversmithing by creating accessories. His attention to detail and quality lead him to be awarded a gold and a silver medal at the 1867 and 1878 Paris World Exhibitions. After 1878, his sons, known as the Keller brothers, succeeded him and moved production to focus more on silverware. Their designs and craftsmanship sold well and at the 1889 and 1900 world fair they received a gold medal and a Grand Prix. Their quality was so good that in 1889, Lucien Falize wrote that "everything stamped Keller is good". At the time Keller fils et gendre successeurs, as they were known was located in Paris at 65 rue de Turbigo before moving their shop and workshop to 22 rue Joubert in 1891. Keller even attracted international customers becoming an appointed official supplier of several courts including Spain, Russia, Greece and Romania. The Russian Court also became an important client and from 1897 made regular purchases from Keller. Keller was also commissioned in the 1900's to produce several important cups and trophies for the Principality of Monaco. After the war the shop moved to 18 Avenue Matignon and records indicate it likely was active as late as 1947.