A Priori were formed in Thessaloniki in the mid '70s. The founding members were Danis Tragopoulos (guitar, piano, vocals), Dimitris Goumberitsis (bass), Sotiris Anadolis (drums) and Dimitris Panagiotidis (guitar). Through the years the band went through several line-up changes.

Their homonymous album was released in 1986. They disbanded in 1991 and reunited just for one concert in 2010.