A 20th Century art form is one of the “things” included in a new display at The State Historical Building.American Jazz will be featured in the wide-ranging “Creations of the 20th Century” display which opens at the State Historical Building next month.Curator Jack Lufkin says jazz is an American institution, a hybrid blend of blues, ragtime and Negro spirituals. Lufkin says Iowa’s Bix Biederbecke played a “huge role” in development of the art form.Swing music was an outgrowth of jazz, and Iowa-born conductor Glenn Miller, who died tragically in World War II, had a role in shaping swing. Miller materials are included in the historical building display, but not the famous trombone, which is at the Miller museum in Clarinda.