Albert Langen (8 July 1869 – 30 April 1909) was a German publisher and founder of the satirical publication Simplicissimus.
Langen was, after Martha and Martin, the third of four children born to Antwerp industrialist Friedrich Albert Langen and Ida Goeters. After the death of Langen's grandfather, Johann Jacob Langen, the family moved to Cologne on Jacordenstrasse 5, where Langen and his siblings grew up and where his younger sister, Elizabeth, was born.
After a clerical apprenticeship, Langen moved to Paris in 1890 to be trained as a painter. There, he became acquainted with many writers, including Henry Becque, Abel Hermant, Paul Hervieu, Octave Mirbeau, and Émile Zola, as well as artists including Théophile Alexandre Steinlen, one of the chief illustrators for Gil Blas Illustré, who was to become a lifelong friend. He also found a mentor in the Dane Julius Rudolph Wilhelm Petersen, who had lived in Paris since 1890 under the name Willy Gretor. Gretor was an outgoing adventurer and con man who as a painter, poet, art dealer, and forger, depicted many images. For a time, Gretor was a secretary for Frank Wedekind, and served as the inspiration behind the Marquis in Wedekind's 1898 play, Der Marquis von Keith. Langen took over Gretor's grandiose apartment on the Boulevard Malesherbes, along with expensive furniture and an extensive collection of images (including some, it was said, of dubious authenticity). Inspired by Gretor, Langen considered opening an art gallery, but an encounter with the author Knut Hamsun, whom he also met through Gretor, led him in a different direction. Hamsun's novel Mysterium had been rejected by S. Fischer Verlag, but Langen was so moved by a German translation of the work (by Marie von Borch) that he offered to pay Samuel Fischer for the printing costs. When this still failed, Langen founded a publishing house to bring out the work himself. Hamsum's Mysteries, thus, came out in 1894 as the first title under the Langen imprint.