Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Date of Award

Fall 2015

Document Type


Degree Name

Master of Arts (MA)


Department of History


Steven Guerrier


In June 1919, President Woodrow Wilson returned from Paris after several months of negotiating the Treaty of Versailles to end World War One. At the peace conference, Wilson achieved his goal of establishing the League of Nations. However, he had one more hurdle: convince the Republican Senate to ratify the treaty. This was no easy task as Republicans claimed the treaty nullified the Monroe Doctrine, even though the century-old foreign policy was recognized, by name, in the League of Nations Covenant. Why, then, did opponents of the League of Nations in the United States claim isolation and refuse to ratify the treaty even though the Monroe Doctrine was included in the diplomatic agreement?

The answer lies with the Republican foreign policy of expansionism that thrust the United States onto the world stage as a colonial power in 1898. Evidence from letters, diaries, and published articles by major Republican leaders, such as Theodore Roosevelt and Henry Cabot Lodge, proves that the United States wished to maintain its authority over the Western Hemisphere and other areas controlled by the colonial power. Further, an examination of the interactions between Democratic and Republican leaders illustrates the urgency with which those opposed to the League placed on the protection of the Monroe Doctrine’s authority within the Western Hemisphere.

While one cannot disregard the political drama that unfolded during the League of Nations debate in 1919, it is necessary to look at a broader picture in order to understand why opponents wished to include the Monroe Doctrine in the treaty and pretend to be in isolation. The conclusion that the United States wished to remain sovereign with authority over the Western Hemisphere provides the notion that Americans wanted to be on par with European imperial powers, but also provides answers as to why many in 1919 argued that the United States was an isolationist nation, even when it clearly was not.