Walter V of Brienne (c.1275 - March 15, 1311), also known as the 'Duke of Athens' , was born in Brienne-le-Chateau, Aube, Champagne, France. He was the son of Hugh Count of Brienne and Isabel de la Roche from Athens, Greece.

Walter V held the titles of Count of Brienne and Lecce, and Duke of Athens. He fought unsuccessfully to defend his claim to Athens after its occupation by Catalan mercenaries known as the Catalan Company in 1311. Despite a life-long dedication to this cause, Walter V was never able to reclaim his Dukedom. He perished in his struggle at the Battle of Halmyros on the river Cephissus in Boeotia in 1311.

In the year 1305 he married Jeanne de Chatillon and had two children:

• Isabel Countess of Brienne (b.1306).
• Walter VI of Brienne, later his succesor (c.1304 - 1356).

References

• Leo's Genealogics Website
• Rootweb World Connect