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Using a Landau–de Gennes approach, we study the impact of confinement topology, geometry and external fields on spatial positioning of nematic topological defects (TDs). In quasi two-dimensional systems we demonstrate that confinement enforced total topological charge m>>1 decays into elementary TDs bearing charge m=1/2. These assemble close to the bounding substrate to enable essentially bulk-like uniform nematic ordering in the central part of a system. This effect is reminiscent of the Faraday cavity phenomenon in electrostatics. We observe that in certain confinement geometries, varying the order parameter correlation length size could trigger global rotation of an assembly of TDs. Finally, we show that an external electric field could be used to drag the boojum finger tip towards a confinement cell interior. Assemblies of TDs could be exploited as traps for appropriate nanoparticles, opening several opportunities for development of functional nanodevices.