The Purpose of the research is to examine the function and process of organization of 'Anti-Imperialist League' in the 19th century. As noted in the study, the members of 'League' consisted of such various groups as lawyers, scholars, politicians, labor reformers, and journalists etc. Basically, the body demonstrated that the nation had enough pressing problems at home without seeking others ; that foreign ventures would divert attention, energy, and funds from the solution of these grave domestic problems. It also indicated that anti-imperialism itself had become essentially a reform movement. Finally, the anti-Imperialists were saying to their countrymen that all Americans should hold the 'doctrines of Liberty' to be seen on the Declaration of Independence.