Isabella d'Este (May 18, 1474 – February 13, 1539) is Marchesa of Mantua and one of the leading women of the Italian Renaissance as a major cultural and political figure.

She is a patron of the arts as well as a leader of fashion, whose innovative style of dressing is copied by women throughout Italy and at the French court.

The poet Ariosto labelsher as the "liberal and magnanimous Isabella", while author Matteo Bandello describes her as having been "supreme among women".

Diplomat Niccolò da Correggio goes even further by hailing her as "The First Lady of the world".

She serves as the regent of Mantua during the absence of her husband, Francesco II Gonzaga, Marquess of Mantua and the minority of her son, Federico, Duke of Mantua.

In 1500 she meets King Louis XII of France in Milan on a diplomatic mission to persuade him not to send his troops against Mantua.

She is a prolific letter-writer, and maintains a lifelong correspondence with her sister-in-law Elisabetta Gonzaga.

Lucrezia Borgia is another sister-in-law; she later becomes the mistress of Isabella's husband.