Margherita Gonzaga (1591-1632), Duchess of Lorraine (detail) ~ by Frans Pourbus the Younger ~ (Netherlands, Antwerp 1569-1622 Paris) ~ Frans Pourbus the younger was a Flemish painter, son of Frans Pourbus the Elder and grandson of Pieter Pourbus. Margherita was born in Mantua, the eldest daughter of Vincenzo I Gonzaga and Eleonora de' Medici.
Portrait of Eleonora di Toledo by Agnolo di Cosimo ("Il Bronzino," Italian, 1503-1572), 1545. What a beautiful dress. If anyone can determine where this painting is held please comment. The source says the national gallery in Prague but a search of their website did not find this painting.