Bertrand d'Argentré

In his judicial capacity, he frequently clashed with other jurisdictions such as that of the Parlement, which he considered ignorant of Breton customs.

His principal legal work is the influential Nouvelle coutume de Bretagne (1580), a compilation of customary Breton law.

In that work, D'Argentré fought against the influence of French and Roman law, which he considered overly procedural and inquisitive, unmerciful to the weak, and detrimental to individual liberty.

The Estates of Brittany commissioned him in 1580 to write a Histoire de Bretagne, which was promptly seized on the order of Henry III for "indignities against King and realm".

[1] In 1589, he supported the insurrection of the Duke of Mercœur, was persecuted by the French authorities and died one year later.