Juan Bautista Martínez del Mazo

Juan Bautista Martínez del Mazo spent his life a step behind the greatest Spanish painter of the age, and copied him so well that scholars still argue over which canvases are really his. He entered the Madrid studio of Diego Velázquez, court painter to Philip IV, around 1630, married the master's daughter Francisca in 1633, and took on his father-in-law's loose, silvery brushwork more completely than anyone else.

When Velázquez died in 1660, Mazo inherited his post as pintor de cámara, painter to the king's own chamber. Much of his work was portraits of the royal family and copies after Velázquez, so faithful that his own hand can be hard to pick out.

He signed very little. One of only two paintings he put his name to is a wide View of Zaragoza from 1647, the northern city spread along the Ebro river under an enormous sky, its townspeople scattered in small knots across the foreground. He held the court post until his own death in 1667.