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We reveal an explicit strategy to design the magneto-optic response of a magneto-plasmonic crystal by correlating near- and far-fields effects. We use photoemission electron microscopy to map the spatial distribution of the electric near-field on a nanopatterned magnetic surface that supports plasmon polaritons. By using different photon energies and polarization states of the incident light we reveal that the electric near-field is either concentrated in spots forming a hexagonal lattice with the same symmetry as the Ni nanopattern or in stripes oriented along the Γ−K direction of the lattice and perpendicular to the polarization direction. We show that the polarization-dependent near-field enhancement on the patterned surface is directly correlated to both the excitation of surface plasmon polaritons on the patterned surface as well as the enhancement of the polar magneto-optical Kerr effect. We obtain a relationship between the size of the enhanced magnetooptical behavior and the polarization and wavelength of optical excitation. The engineering of the magneto-optic response based on the plasmon-induced modification of the optical properties introduces the concept of a magneto-plasmonic meta-structure., E.Th.P. acknowledges Carl Zeiss Foundation for financial support. A.G.-M. acknowledges the Spanish Ministry of Economy and Competitiveness (Contract No. MAT2014- 58860-P) and the Comunidad de Madrid (Contract No. S2013/MIT-2740). P.T. acknowledges financial support through the Excellence Initiative (DFG/GSC 266). V.K. acknowledges financial support from the Knut and Alice Wallenberg Foundation. We thank Piotr Patoka for the preparation of the polystyrene bead template. We gratefully acknowledge the Deutsche Forschungsgemeinschaft program SFB/TRR 173: SPIN+X.