Simon I de Montfort
Seigneur of Montfort
Reign	1053–1087
Predecessor	Amaury I de Montfort
Successor	Amaury II de Montfort
Born	c. 1025 Montfort l'Amaury, Kingdom of France
Died	25 September 1087(1087-09-25) (aged 61–62)
Buried	Épernon, Kingdom of France
Noble family	House of Montfort
Spouse(s)	Isabel de Broyes Agnes d'Evreux
Issue	Bertrade de Montfort Richard de Montfort Simon II de Montfort Amaury III de Montfort Guillaume de Montfort Adeliza de Montfort
Father	Amaury I de Montfort
Mother	Bertrade

Simon I of Montfort or Simon de Montfort (c. 1025 – 25 September 1087) was a French nobleman. He was born in Montfort l'Amaury, in the Duchy of Normandy, and became its lord. He was the son of Amaury I de Montfort^[1] and Bertrade. At his death he was buried about 20 miles (32 km) away in Épernon, because it was the site of the fortress he was instrumental in constructing.

Progeny

Simon I first married Isabel de Broyes (b. 1034 in Broyes, Marne),^[2] daughter of Hugh Bardoul. Their children were:

• Amaury II de Montfort (c. 1056 – 1089),^[3] lord of Montfort
• Isabel (Elizabeth) de Montfort (b. 1057), who married Raoul II de Tosny,^[3] a companion of William the Conqueror.

Simon I's second marriage was to Agnes d'Évreux (b. 1030), daughter of Richard, Count of Évreux.^[4] Their children were:

• Bertrade de Montfort (c. 1059 – 1117), became queen of France.^[5]
• Richard de Montfort (c. 1066 – 1092), lord of Montfort, slain in attack on abbey at Conches.^[6]
• Simon II de Montfort (c. 1068 – 1104), lord of Montfort^[7]
• Amaury III de Montfort (c. 1070 – 1137), lord of Montfort^[7] and Count of Évreux.
• Guillaume de Montfort (c. 1073–1101), bishop of Paris.^[7]
• Adeliza de Montfort (b. 1075)