Found some history.
The Union Zouaves
Mustered in October 2, 1861.
Company B.
This company was recruited in the city of Reading, and had been organized previously as one of the Home Guard regiments. It was commanded by Capt. John E. Arthur, a brave soldier of the Mexican War, and his Lieutenants were originally G. S. Kinsey, 1st Lieutenant and John Teed, 2d Lieutenant. The company on Saturday, October 12, 1861, elected
Darius G. Rhoads their 2d Lieutenant a very good selection in place of Lt. Teed, resigned. The company was mustered in service on Wednesdays October 2, 1861.
The 91st Pennsylvania Volunteer Infantry was a Union infantry regiment which fought in multiple key engagements of the American Civil War, including the Battle of Fredericksburg, Battle of Chancellorsville and Battle of Gettysburg. It was established through the combined efforts of Edgar M. Gregory, who had received approval from the U.S. War Department to begin recruiting soldiers for an entirely new regiment during the fall of 1861, and Edward E. Wallace, who had initiated his own recruitment efforts that October. Their recruits were volunteers, the majority of whom initially enlisted for three-year terms of service from their hometown of Philadelphia; they were divided into 10 lettered companies upon muster in during early December 1861: A, B, C, D, E, F, G, H, I, and K. (In later years, as the war dragged on and the need for reinforcements arose, additional men were drafted from communities across the state.)
The men who enrolled with the 91st Pennsylvania wore modified Zouave uniforms (dark blue Zouave-style jacket and vest with yellow trim, sky blue sash, sky blue pantaloons, and red fez with blue tassel).[2] The regiment's leaders were presented with the unit's First State Color on December 6, a flag which had been manufactured by Horstmann Brothers and Company.
After serving for almost four years, they officially mustered out on July 10, 1865, and disbanded upon their return to Philadelphia.
91st Pennsylvania Volunteer Infantry at Camp Northumberland, Virginia, 1861 (Matthew Brady, Metropolitan Museum of Art).