(June 1, 1859 or 1860? - February 20, 1939) Germany.
Francine Cocard says Peter Lambert was a breeder from Trier/Trèves a few kilometers form the German-Luxembourgish border. He was married to a Luxembourgish lady and had good contacts with Luxembourgish breeders. Some of his rose were also sold by the Luxembourgish breeders, Soupert & Notting, Gemen-Bourg, and Ketten Freres...
Thank you, Francine!
[From The Gardener's Chronicle, 1939, p. 158:] "The death occurred, on February 20, of one of the best known and most famous Rose growers - Peter Lambert, of Trier, in Germany. He was in his eightieth year, and succumbed after a short ilness. Lambert rose to fame in 1891 with the production of his novelty Kaiserin Auguste Victoria, and gained even greater renown two years later with the production of Frau Karl Druschki...."
[From The Ultimate Rose Book, by Stirling Macoboy, p. 459:] A turn-of-the-century German hybridist, still celebrated for 'Frau Karl Druschki' (1900) and 'Gartendirektor Otto Linne' (1934). He also raised a series of Shrub Roses called 'Lambertianas', and 'Trier', which is an ancestor of most of the Hybrid Musks.
[From My World of Old Roses, Vol. 2, p. 103:] The idea of creating this wonderful collection of roses [at Sangerhausen] was conceived by Peter Lambert in 1897, becoming a reality in 1903.