Walter III, Count of Brienne

Walter III of Brienne (died June 14, 1205) was the Count of Brienne 1191–1205, Prince of Taranto, Duke of Apulia, and Count of Lecce, and titular King of Sicily 1201–1205. He was the son of Erard II of Brienne and Agnès of Montfaucon.

In 1200 he married Maria, daughter of Tancred of Sicily and sister and heiress of the deposed king William III of Sicily. Her precise name is unclear but has been given variously as Mary, Elvira, Albiria, Albinia, or Blanche. She died after 1216. At the time of their marriage, she and her family were exiles in France, trying to find allies to reclaim the Kingdom of Sicily from the young King Frederick. As her husband, Walter was recognized by Pope Innocent III as Prince of Taranto, Duke of Apulia, and Count of Lecce. After the Battle of Agnella in 1201, he took the title of King of Sicily. In 1204, he was besieged in the fortress of Terracina by Diepold of Vohburg and lost an eye to an arrow, but he broke the siege and put Diepold to flight. On June 11, 1205, he was ambushed by a sally of Diepold's while besieging him at Sarno and mortally wounded. He died in German hands on June 14, 1205, and was buried at the church of St. Maria della Foce in Sarno.

In 1205, his widow gave birth to his son

• Walter IV of Brienne; but he received only the County of Brienne, his Sicilian inheritance having been confiscated because of his father's rebellion.

His daughter

• Anais, married Balian I Grenier, Lord of Sidon, and was also a mistress of Frederick II.

His widow Elvira married secondly Giacomo Sanseverino, Count of Tricarico, and thirdly Tigrini Guidi, Count of Modigliano (or Count Palatine in Tuscany?)

Preceded by Robert	Prince of Taranto 1200–1205	Succeeded by Frederick II
Preceded by Erard II	Count of Brienne 1191–1205	Succeeded by Walter IV