Regent of Milan
Caterina was born in Milan, one of the seventeen children of Bernabò Visconti, Lord of Milan, and Beatrice Regina della Scala (1331 – 18 June 1384). Her paternal grandparents were Stefano Visconti, Lord of Milan, and Valentina Doria, and her maternal grandparents were Mastino II della Scala and Taddea da Carrara.
Her niece, Isabeau of Bavaria, daughter of her eldest sister, Taddea, was a Queen consort of France upon her marriage in 1385 to King Charles VI. Following the murder of her maternal grandfather, Isabeau became one of the most implacable enemies of Caterina’s husband Gian Galeazzo and his daughter, Valentina, Duchess of Orleans.
Early in 1379, a possible marriage was discussed between Caterina and King Richard II of England. The King’s tutor and advisor, Sir Simon Burley went to Milan to negotiate, but he had misgivings about the match. Bernabò also rejected it, as he favoured another alliance for his daughter. On 2 October 1380, in the Church of San Giovanni in Conca, at the age of about nineteen, Caterina married her first cousin, Gian Galeazzo Visconti, whose first wife Isabelle of Valois had died in 1373 in childbirth, leaving him three sons who all died young, and a daughter, Valentina Visconti, who, in 1389, married Louis, Duke of Orleans. From Isabelle, Gian Galeazzo had inherited the title of Count of Vertus in Champagne.
In 1385, Gian Galeazzo deposed Caterina’s father, Bernabò as Lord of Milan. Bernabò was imprisoned at the Castle of Trezzo where he was allegedly poisoned on orders of Gian Galeazzo. Caterina became the Duchess of Milan on 11 May 1395, when her husband was created the first duke by Wenceslaus, King of the Romans for 100,000 florins. To commemorate the event, a missal was painted by Anovelo da Imbonate, depicting, in the foreground, the kneeling figures of Caterina and Gian Galeazzo. It is now in the library of the Basilica of Sant’Ambrogio in Milan. Her husband granted her the castle of Monza and the signoria of Vicenza. Caterina and her husband commissioned the construction of the Certosa di Pavia, which began on 27 August 1396.