Recently, the so called Belavin-Drinfeld cohomologies (twisted and untwisted) have been introduced in the literature to study and classify certain families of quantum groups. The purpose of this talk is to interpret these cohomologies in terms of usual Galois cohomology. This allows the full power of this theory to be brought to bear. As a consequence, several results that were known to hold in particular cases by means of computational proofs, can now be established in full generality by theoretical considerations.