Saint-Rémy, September 1889.
Van Gogh painted over 30 self portraits between the years 1886 and 1889. His collection of self portraits places him among the most prolific self portraitists of all time. Van Gogh used portrait painting as a method of introspection, a method to make money and a method of developing his skills as an artist.
See van Gogh's self portraits in chronological order at http://www.wga.hu/html_m/g/gogh_van/16/ .