We report on a study of the magnetic domain coupling in epitaxial wedge-shaped Fe layers deposited onto CoO/Ag(001). By using photoelectron emission microscopy (PEEM) in combination with x-ray magnetic circular and linear dichroism (XMCD, XMLD), we imaged the ferromagnetic and antiferromagnetic domains present in the Fe and CoO layers, respectively, below the CoO magnetic ordering temperature. The uncompensated Co spins at the Fe/CoO interface were revealed by XMCD-PEEM and were found to be coupled parallel to the magnetization of the Fe layer. An increase of the CoO XMLD contrast is visible for Fe thicknesses below 2 ML, where the Fe layer lacks magnetic long-range order.