Agnes I (1170 – in 1192 or 1193 in Mailly), was the reigning Countess of Nevers, Auxerre and Tonnerre between 1185 and 1192.
She was the daughter of Guy, Count of Nevers, Auxerre and Tonnerre, and Mathilde de Burgundy, dame of Montpensier.
[1] Heiress of the counties of Nevers, Auxerre and Tonnerre at the death of her brother William V in 1181,[2] she was initially married to Olivier "Albus," lord of Grignon († 1181/84).
[2] When Olivier died, King Philip Augustus arranged her marriage in 1184 - she was 14 - with Peter II of Courtenay.
[2] She died in 1192 or 1193, while her husband fought in the Holy Land with the Third Crusade, leaving a daughter, Matilda (1188 † 1257),[2] Countess of Nevers, Auxerre and Tonnerre, who married with Hervé IV of Donzy († 1222) in 1199,[3] and in 1226 with Guigues IV of Forez († 1241).