Career
In 1179, Roger II Trencavel, Raymond V of Toulouse, and Bernard Ato had all been excommunicated by Pons d"Arsac under the twenty-seventh canon of the Third Lateran Council for their lack of strong opposition to heresy. In that same year Bernard Ato did homage to Alfonso II of Aragon for his viscounties and made an alliance with Alfonso against Raymond V.
In June 1187, Bernard Ato granted all his lands within the Diocese of Agde (omnes dominationes vicecomitatus) to the diocese and was then accepted into the cathedral church as a canon. In July the donation was confirmed by Raymond V and in August Bernard Ato also, in an extensive charter.
The viscounty was de facto handed over to the bishop.
He is also said by some authors to have given over Nîmes to Raymond in that year, but this is contradicted by other sources. Bernard Ato swore fealty to William VIII of Montpellier for part of his domains in 1189, January 1191, and finally 1195.
