Electromagnetic force actuated plasmonic nonlinear metamaterials have attracted a great deal of interest from the scientific community over the past several years, owing to the abundant interactions between the electromagnetically induced Ampère's force and the stored mechanical force within the meta-atoms. Despite this interest, a comprehensive study of such metamaterials is still lacking, especially for the nonlinear coupling states analysis. Here we fill this gap by extensively studying the physics of electromagnetic force actuated plasmonic nonlinear metamaterials and presenting a number of new significant findings. Our study will help physicists and engineers to better understand this hot topic and stimulate rapid developments of this promising nonlinear metamaterials.