6This report provides a narrative account of four battles within Operation Inherent Resolve (OIR) and a review of U.S. ground force contributions to those battles. It is intended to serve as an operational history and review of warfighting functions as applied to OIR. Although OIR was both a Coalition fight and joint one, the focus on U.S. ground forces is meant to address gaps both in analysis and in the common understanding of OIR.