Jan III van Brabant, also called John III the Triumphantor, was born in 1300 and died in Brussels on December 5, 1355. He was Duke of Brabant and Limburg (1312-1355) and Duke of Lorraine. He was the son of John II of Brabant and his wife Margaret of England, daughter of King Edward I of England.

He married Marie d' Evreux, who died on October 31, 1335, the daughter of count Louis d'Evreux and Marguerite d'Artois.

During the reign of Jan III, Brabant was an ally of England. Jan III fought many wars and became powerful. As a result some sovereigns in the Low Countries became his enemies from 1329 til 1334, among them Flanders, Liege, Holland and Gelre. The sovereigns were stimulated by Philip VI of France. During the peace of Amiens the French king declared that Jan III of Brabant had to hand over the cities of Tiel, Heerewaarden and Zandwijk to the county of Gelre. However it was able to annex the enclave of Mechelen which belonged to Liege. In 1350 persecution of Jews in Brabant.

After his death Jan III was buried in the Cistercian Abbey of Villers (now in Belgium).

Preceded by:
John II
Duke of Brabant Succeeded by:
Joan