Margherita de' Medici

Margherita de' Medici (31 May 1612 – 6 February 1679) was Duchess of Parma and Piacenza by her marriage to Odoardo Farnese, Duke of Parma. Margherita was regent of Plaisance in 1635 and regent of the entire duchy in 1646 after the death of her husband. 
Family.
She was the fourth of eight children and the second daughter born to Cosimo II de' Medici, Grand Duke of Tuscany and his wife Maria Magdalena of Austria. 
Margherita's siblings included Ferdinando II de' Medici, Grand Duke of Tuscany, Cardinal Gian Carlo de' Medici, Cardinal Leopoldo de' Medici and Anna, wife of Ferdinand Charles, Archduke of Further Austria. Margherita's other siblings died in childhood or eary adulthood. 
Margherita married Odoardo Farnese, Duke of Parma on 11 October 1628. On 11 September 1646 Odoardo died. Their eldest son, Ranuccio was not yet old enough to rule the Duchy alone so Margherita acted as regent until her son was old enough to govern alone. She died in Parma on February 6 1679.