Joanna of Gallura

Joanna (or Giovanna) Visconti (died 1339) was the titular Judge (Giudicessa) of Gallura from 1298. She was the daughter of Ugolino Visconti and Beatrice, daughter of Obizzo II d'Este. She succeeded her father when she was a baby, though he had already been deprived of Gallura by the Republic of Pisa at the time and her succession was purely nominal.

She claimed her rights in Sardinia to no avail and eventually sold them to her relatives, the Visconti of Milan, who later sold them to the Crown of Aragon. On 13 November 1309, she married Rizzardo da Camino, Count of Ceneda and Lord of Treviso. In 1328, she was granted a pension by the Guelphs.

She is mentioned passingly by Dante Alighieri in Purgatorio Canto VIII:46–84, where her father, a friend of Dante's, but consigned to Purgatory with the other negligent rulers, asks her to be reminded of him.