Who posed for The Girl with a Wine glass painting?

Not a single sitter in Vermeer’s painting has ever been identified. The most obvious candidate would be Janet Vogel whose coat of arms stands out on the opened window. However, documents show that she had died eight years before Vermeer was ever born. Another candidate might be Maria de Knuijt, the wife of Vermeer’s wealthy Delft patron, Pieter van Ruijven, since it is extremely likely that this painting was part of their family collection. We know that in Maria’s will she bequeathed to Vermeer 500 florins. This sum was comparable to the cost of from one to three expensive cabinet pictures. Such a bequest, made to a painter, who was not a family member, to be possibly unique. It thus counts as a gesture of special esteem and commitment to the painter’s well-being. Maria de Knuijt might have been acting on behalf of her husband, but she evidently had brought the far greater share of money to the marriage, and her taste must have been taken into account. As a supporter of the Orthodox wing of the Reformed church, De Knuijt might have found particularly appealing the chaste dignity that informs Vermeer’s interpretations of femininity.

Reference – http://www.essentialvermeer.com/catalogue/girl_with_a_wine_glass.html#