Service flags were commonly hung in windows of homes during World War I. A blue star represented a soldier currently in the service, and a gold star represents a soldier killed while in the service. 

This flag was used by the Lewis Park Union of the Women's Christian Temperance Union in St. Paul. The gold star is for David Neary, who was killed in France on July 19, 1918. The other 27 stars were for men from that community who were serving in World War I, including a few sets of brothers.