Civil War regiments were usually composed of companies from the same state and most of the time from the same county. Due to the unique and high standards to join the Sharpshooters, each regiment was formed with companies from different states. The organization of the two Sharpshooter regiments by company is listed below with the names of the original commanding officers (all captains).
1st Regiment US Sharpshooters
Company A - New York (Casper Trepp)- in New York City September, 1861
2nd Regiment US Sharpshooters
Company A - Minnesota (Francis Peteler)- October 5, 1861
Most of Regiment concentrated at Weehawken, N.J., September, 1861, and moved to Washington, D.C., September 24-25.
Mustered in November 29, 1861
Served Unattached, Army of the Potomac, and Martindale's Brigade, Fitz John Porter's Division, Army of the Potomac, to March 1862.
3rd Army Corps, 1st Division, Unassigned, Army of the Potomac, to May 1862.
5th Army Corps, 1st Division, 3rd Brigade, to March 1863.
3rd Army Corps, 3rd Division, 3rd Brigade, to June 1863.
3rd Army Corps, 1st Division, 2nd Brigade, to September 1863.
3rd Army Corps, 1st Division, 3rd Brigade, to March 1864.
2nd Army Corps, 3rd Division, 2nd Brigade, to December 1864.
The last action of the 1st Regiment USSS was "Deep Run" or "Four-Mile Creek" on August 15-16, 1864. Terms of service would now start expiring for men in the Companies of the 1st Regiment. The 1st Regiment started it's "mustering out" with the "Swiss Company A" on August 18th, followed by Company C on August 20th and Company B on August 28th. During September, Companies E, F, G and H were mustered out, leaving only companies, D, I and K. Men whose enlistment hadn't expired stayed with 1st Regiment Companies until Companies D, I and K were mustered out during November and December 1864. For a short time in December the remaining companies with recruits and veterans, formed a consolidated battalion. On December 31st 1864 this battalion was transferred to the 2nd Regiment USSS, except for the men from Michigan who joined the 5th Michigan Infantry Regiment. The 2nd Regiment USSS remained intact until February 20, 1865 when men whose term of enlistment hadnít expired were sent, in most cases to regiments of their respective states. New York men joined the 124th NYSV Infantry Regiment; Company G joined the 36th Wisconsin; Company A joined the 1st Minnesota, etc.