Duke-Bishop

The Peerage of France (French: Pairie de France) was a hereditary distinction within the French nobility which appeared in 1180 in the Middle Ages, and only a small number of noble individuals were peers. It was abolished in 1789 during the French Revolution, but it reappeared in 1814 at the time of the Bourbon Restoration which followed the fall of the First French Empire, when the Chamber of Peers was given a constitutional function somewhat along British lines, which lasted until the Revolution of 1848. On 10 October 1831, by a vote of 324 against 26 of the Chamber of Deputies, hereditary peerages were abolished, but peerages for the life of the holder continued to exist until the chamber and rank were definitively abolished in 1848.

The prestigious title and position of Peer of France (French: Pair de France) was held by the greatest, highest-ranking members of the French nobility. French peerage thus differed from British peerage (to whom the term "baronage", also employed as the title of the lowest noble rank, was applied in its generic sense), for the vast majority of French nobles, from baron to duke, were not peers. The title of 'Peer of France' was an extraordinary honour granted only to a small number of dukes, counts, and princes of the Roman Catholic Church. It was analogous to the rank of Grandee of Spain in this respect.

The French word is equivalent to the English "peerage". The individual title, in French and "peer" in English, derives from the Latin par, "equal". It signifies those noblemen and prelates considered to be equal to the monarch in honour (even though they were his vassals), and it considers the monarch thus to be primus inter pares, or "first among equals".

...
Wikipedia