The aforementioned Chicago Highland Guard is mentioned here:

THE WASHINGTON INDEPENDENT REGIMENT was commanded by Lieutenant-Colonel Thomas Shirley, its colonelcy being vacant by the death of Colonel William H. Davis. It's Major was W. H. Wallis, and there were no other regimental officers. It's companies were the Highland Guards, Washington Light Cavalry, Washington Rifles, Washington Grenadiers, and the Black Jager Rifles. These two regiments formed the Second Brigade of the Sixth Division, Illinois State Militia, commanded by Brigadier-General R. K. Swift, who had three aides with rank of major. These were William S. Johnson, Jr., John Ross and E. W. Griffin. Major Charles B. Brown was quartermaster. In January, 1861, the status of these several companies, formerly the pride and glory of Chicago was anything but satisfactory. The old militia system had borne heavily on both the time and finances of men and officers, and as the belief had been forced upon all that the showy glories of parade and drill did not compensate for a depleted purse or the possible neglect of more important duties, the military spirit had gradually died out, and the drill room had been abandoned.

-- http://www.taylorsbattery.org/Pre%20...0formation.htm