The Battle of Schrute Farms was a codename for a gathering of artists and poets during the Civil War in The Office.

Initial Speculation

In the episode Gettysburg, Dwight argues with Oscar about what he claims is the northernmost battle of the Civil War: The Battle of Schrute Farms. Dwight maintains that its absence from the history books is an example of re-writing history, whereas Oscar maintains that the battle is a fictitious creation

The TRUE History of Schrute Farm - The Office US

Discovery of Origin

After tracking down a historian, Dwight and Oscar learn that the Battle of Schrute Farms did in fact take place. However, the "battle" was really a code term. During the Civil War, Schrute Farms was a safe haven for artists and poets (and, as heavily implied, homosexuals). Oscar finds this fascinating, whereas Dwight leaves in disgust.