Jakob Plein-Wagner (1836-1903) was a German potter and entrepeneur. He established the company "Jac. Plein-Wagner-Söhne, Steinzeugfabrik in Speicher" in 1901, so only two years before his death, although he had been active as a potter for many years already.
An extensive description of Jakob (Jacob) Plein-Wagner's life and work can be found here.
Last known address:
The company produced salt-glazed products such as pots, steins, and kitchenalia.