In 1457 de Brézé was exercising the original functions of the office in the Échiquier. Six years before, as the commissary of the King in place of Dunois, he had brought before the Assembly of the Province the vital questions of the confirmation of the Charte aux Normands, of the installation of a special financial machinery for the Province, and other measures necessary at the resumption of authority by the French. Though he fell temporarily into disfavour with Louis XI., and was obliged to consent to the marriage of his son Jacques with Charlotte, daughter of Charles VII. and Agnes Sorel, he resumed his post of Grand Seneschal on returning from his wars in England, and died in office.
His son Jacques de Brézé, Comte de Maulévrier, inherited the same distinction; but having killed his wife, whose birth had shown its unfortunate effects too soon in flagrant infidelity, he was in turn disgraced and fined, but in turn was also reinstated. His son Louis de Brézé was given the apparently imperishable family heirloom of the office of Grand Seneschal in August 1490, and the great seal of the Sénéchaussée of Normandy was henceforth his coat of arms. More of a soldier and a courtier than a man of law or of finance, this de Brézé left the duties of his office to a numerous staff, whose names have been preserved in the registers of Rouen. He married first Catherine de Dreux, "dame d'Esneval," and left his brother-in-law in charge of the duties of his office, when he left it. During this period it was that Cardinal d'Amboise organised the Supreme Court of the Échiquier de Normandie (of which Antoine Bohier, Abbé of St. Ouen, was a member), in the last years of Charles VIII., which, when the Duc d'Orléans became Louis XII., was to blossom into the Perpetual Échiquier in the new "Palais de Justice."
The organisation of this court did away with any practical necessity for a Grand Seneschal, but Louis de Brézé was still allowed to keep the honour of the title, and even to take a seat in the court, which was soon to be called the "Parlement de Normandie" by François Premier. Louis de Brézé's second wife was the famous Diane de Poitiers, who called herself "La Grande Sénéschale" until she died, and who put up the magnificent tomb in alabaster and black marble which has preserved her husband's memory ever since his death in 1531, long after the "Palais de Justice" had been built to carry on for ever those legal functions which had once been a portion of the duties of his office.