Hexagonally arranged dense monodispersed iron oxide, cobalt oxide and cobalt iron oxide nanoparticle arrays are generated using block copolymer (BCP) inclusion methodology on substrate. Polystyrene-b-poly(ethylene oxide) (PS-b-PEO) BCP nanopatterns forming perpendicularly oriented PEO cylinders is used as a structural template. The PEO microdomains are modified by ethanol which selectively incorporate metal ions through chemical coordination. The formation of oxides and composites and removal of polymers is performed by UV/Ozone treatment. The precursor-solution concentrations and aging time are tuned to create uniform diameter, ordered monodispersed nanoparticles. The stability of the oxides is investigated by high temperature calcination. XPS reveals the phases of as-prepared oxides and after annealing. The cation distribution is determined for the nanocomposite, from curve fitted Co 2p and Fe 2p spectra, (Co_0.4Fe_0.6)[Co_0.6Fe_1.4]O₄ corresponds to cobalt ferrite, CoFe₂O₄ represent cations in tetrahedral and octahedral sites respectively. The diameter, height, defectivity of nanoparticle arrays for all the oxides are examined.