In August, Brig. Gen. Douglas MacArthur assumed command of the 84th Infantry Brigade which consisted of Neibaur's 167th Infantry Regiment and the Iowa National Guard 168th Infantry Regiment. In early September General John Pershing, commander of the AEF, received permission to "reduce" the salient that had developed for several years at Saint-Mihiel, southeast of Verdun. Beginning on September 12, 1918, the American 1st Army under Pershing commenced an offensive, the first independent American offensive in its own sector of the Western Front. Within days, the crumbling German army was thrown back and the salient was reduced causing a "straightening" of the front line.