This presentation explores the instrumental functions of nationalistic and patriotic rhetoric during the Civil War. Using an innovative text-mining technique called topic modeling to analyze the entire runs of the Richmond Daily Dispatch and the New-York Times during the war, it suggests that the two newspapers used the same language of patriotism and nationalism but to different ends: the former to draw men into the army, the latter to draw voters to the polls to support the Republic Party.  It also reflects upon the broader methodological value of topic modeling, suggesting how cultural and intellectual historians can use the technique to interpret the concrete political, social, and emotional functions of elusive ideological discourses.