 Mir Geribert was related to both the counts and viscounts of Barcelona, being a son of viscount Geribert II and Ermengard, daughter of Count Borrel II.His powerbase lay in the Penedès, where he had many castles, chief among them Olèrdola.Despite his wide-ranging possessions in that region, he had been marginalised as a member of a cadet branch of the vicecomital dynasty and was unwilling to accept his second-tier position within the Penedès or his exclusion from the familial possessions in La Guàrdia and Barcelona.