Bartholomeus Jansz. Molenaer was a Dutch Golden Age genre painter born around 1618 in Haarlem, Netherlands. He came from an impoverished family, being one of eight children born to Jan Mientsen Molenaer, a tailor, and his second wife Grietgen Adriaensdr.

Molenaer grew up in an artistic family, with two of his brothers also becoming painters. His older brother Jan Miense Molenaer was a portraitist and genre painter, while his other brother Nicolaes Molenaer specialized in landscape painting.

On September 4, 1640, Bartholomeus Molenaer joined the St. Luke’s Guild of painters in Haarlem, marking the beginning of his professional career as an artist. The following year, in 1641, he married Cuyniera Hendricx Vrije, with whom he had four children: Frans, Jan, Maria, and Claes.

Molenaer’s artistic style was heavily influenced by prominent Dutch genre painters of his time, including Adriaen Brouwer and Adriaen van Ostade, as well as his brother Jan Miense. He specialized in genre scenes, typically depicting peasants in taverns or students in school settings. Molenaer often signed his works with his own monogram “B.Mr” but was also known to use the initials of other artists, such as “AB” to imitate Adriaen Brouwer, a common practice at the time.

Throughout his career, Molenaer maintained close ties with his family. He lived with his brother Jan Miense and sister-in-law Judith Leyster on Lombaertsteech (now Lombardsteeg) in Haarlem until 1646. His workshop was located in his mother-in-law Maritge Claesdr’s house on Kleine Houtstraat.

Bartholomeus Molenaer’s life and career were cut short when he died on September 8, 1650, in Haarlem at the age of approximately 32. Despite his relatively brief career, his works can be found in various museums worldwide, including the Mittelrhein-Museum in Koblenz, the National Museum in Stockholm, and the Worcester Art Museum.