Treaty of Meerssen
In the early Middle Ages the Diocese of Cambrai was included in that part of Lotharingia which at first had been allocated to the West Frankish king Charles the Bald by the Treaty of Meerssen of 870 but, after various vicissitudes, came under the rule of the German king Henry the Fowler in 925. After the revolt by Duke Gilbert of Lorraine collapsed at the Battle of Andernach of 939, Louis IV of France renounced the Lotharingian lands, and in 941 Henry's son and successor King Otto I of Germany ratified all the privileges that had been accorded to the Bishops of Cambrai by the Frankish rulers.