[en] Two-dimensional crystallization of charged paramagnetic colloidal particles by adjusting the coupling parameter was investigated using digital video microscopy. A phase transition from a dispersed distribution to a highly ordered colloidal crystal was achieved when we adjusted the electro and magnetostatic interparticle interactions. The crystallization process of the colloidal monolayer was characterized quantitatively in terms of the radial pair distribution function. The subtle competition between the repulsive interparticle potential energy and thermal excitations of the particles determines the crystallization of the colloidal system. The results can help us understand the underlying mechanisms of electromagnetic colloidal systems' phase transitions and to fabricate colloidal crystals