During World War I Jameson edited historical material for soldiers in their training camps, and he published articles in the AHR that supported the Allies. In 1918, he was one of two scholars who pronounced on the authenticity of the
Sisson Documents that purported to demonstrate that Germany had financed the
Bolshevik Revolution. Decades later
George F. Kennan demonstrated the documents were forgeries and denounced Jameson for his participation despite his lack of qualifications, notably no knowledge of Russian. At Carnegie Jameson supervised a series of documentary publications, such as guides to archival resources around the world, documentary editions of the letters of members of the Continental Congress, documents on the slave trade and slave law, and the papers of Andrew Jackson, as well as an atlas of American history. Jameson began numerous annual publications and, with
Waldo Leland, started lobbying Congress to create the
National Archives, the building for which was first funded in 1926. The National Archives organization was established in 1934. In 1926 he finally published an influential short book in the works for three decades,
The American Revolution Considered as a Social Movement. After losing his position at Carnegie in 1928, he became head of the Division of Manuscripts at the Library of Congress, where he made some notable acquisitions of major collections. Jameson himself explained his life's work in this way: :"I struggle on making bricks without much idea of how the architects will use them, but believing that the best architect that ever was cannot get along without bricks, and therefore trying to make good ones." ==Honors and tributes==