Maria Gonzaga or Maria of Mantua (29 July 1609 – 14 August 1660) was an Italian princess of the House of Gonzaga: she was Regent in Mantua during the minority of her son from 1637 until 1647, and reigning sovereign duchess of Montferrat from 1612 until 1660.

Maria was the eldest and only surviving child of Francesco IV Gonzaga, Duke of Mantua and Montferrat and Margaret of Savoy (1589–1655), daughter of Charles Emmanuel I, Duke of Savoy and Infanta Catherine Michelle of Spain.

Her father died aged 26 in 1612 when she was only three years old, and was succeeded as Duke of Mantua by his two brothers, who had no issue. This made Maria and her husband Charles of Nevers in 1627 successors to the two Duchies. Maria was already Duchess of Montferrat since 1612.
This led to the War of Mantuan Succession.
The outcome was that, after the death of her husband Charles in 1631, his father Charles became the new Duke of Mantua until his death in 1637.

Maria and Charles had two children:

Maria exercised the regency of Mantua on behalf of her son for ten years, until 1647.
She died in 1660, aged 51.

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