Johann Closterman: A Portraitist of Distinction Johann Closterman (also spelled cloosterman, klosterman; 1660 – 24 may 1711) stands as a significant figure in the landscape of Westphalian portrait painting during the late Baroque and early Rococo eras. Born in Osnabrück, Germany—a city steeped in medieval history and nestled within the Holy Roman Empire—Closterman’s artistic journey began under the tutelage of his father, who instille…