The Scandinavian Caledonides are much more affected by postcontractional Devonian extension than previously thought. The extensional deformation is not restricted to the internal parts of the orogen, but can be traced for more than 200 km from the west coast of Norway toward the foreland. It involved significant reactivation of the basal thrust zone as a low-angle extensional detachment, whic consequently contains abundant top-to-the-(north)west sense of shear indicators. The extensional deformation involved substantial backsliding of the orogenic wedge (eduction of the Baltic shield) together with stretching of the basement by west-dipping, extensional shear zones. After ∼30 km of backsliding, the extensional detachment splayed to penetrate the overlying orogenic edifice in the coastal region in southern Norway, which led to inactivation of the main portion of the basal thrust zone as an extensional detachment.