Countess Charlotte Flandrina of Nassau (Antwerp, 18 August 1579 – St.Croix (near Poitiers), 16 April 1640) was the fourth daughter of William the Silent and his third spouse Charlotte of Bourbon.
After her mother's death in 1582 her French grandfather asked for Charlotte Flandrina to stay with him. She became a Roman Catholic and entered a convent in 1593.
Charlotte Flandrina: biography on Worldroots