The manufacturing cell design problem is part of the cellular manufacturing system and it has been widely studied as an optimization problem. It consists of grouping machines in parts into manufacturing cells in order to minimize the inter-cell movements. In recent years, different approximate methods have been used to solve this problem. In this paper, we propose a new approximate method inspired on the phenomenon of the colonial age, called imperialist competitive algorithm. In the colonial age, the most powerful countries competed to conquer colonies for increasing their power, where the country with highest power was considered the imperialist one. We performed several experiments on a set of 90 instances, where the proposed approach is able to produce optimal values for the whole set of tested instances.