Jean Ier of Thouars , it was born after 1284 and it dies on May 25th 1332. It is the son of Guy II and Marguerite de Brienne.

• 27th Viscount of Thouars: 1308-1332

It succeeds his father Guy II, it died on May 25th, 1332.

He married in 1307 White of the Brabant (girl of Godefroy of the Brabant and Jeanne d' Ascot) which dies in 1330. They had three wire:

• Louis Ier which follows,
• Jean de Thouars, lord of the Cheze-the-Viscount who married Marguerite de Parthenay,
• Guy de Thouars, who dies in 1354, it had married Jeanne de Maulevrier.