Here's some information for your Harvey Fowler:
Name: Harvey Fowler
Enlistment Date: 17 Jan 1865
Enlistment Place: Sacramento, California
Enlisted as a Private on 17 January 1865.
Enlisted in Company I, 2nd Infantry Regiment California on 17 Jan 1865.
Mustered Out Company I, 2nd Infantry Regiment California on 10 May 1866 at Presidio, San Francisco, CA.
He applied and received a Union veteran's pension in 1890. The pension application files, many times, have a great deal of personal, family and residence information.
You can order both his service record and pension application file through the link below.
I have included a history of the 2nd California Infantry below.
Second Infantry CALIFORNIA
Second Infantry. -- Cols., Francis J. Lippitt, Thomas F. Wright; Lieut.Cols., James N. Olney, Thomas F. Wright, Robert Pollock; Majs., James F. Curtis, Thomas F. Wright, John C. Schmidt.
This regiment was organized at San Francisco from Sept. to Dec., 1861, except Co. F. which was organized at Carson City, Nev. It was mustered into the U. S. service at San Francisco Oct. 2 - Dec. 31, 1861, for three years.
Col. Lippitt was promoted brevet brigadier-general, March 13, 1865, for faithful service during the war. Col. Wright, a son of Brig.-Gen. Wright, commanding the Department of the Pacific, was also made brevet brigadier general, March 13, 1865, for faithful service during the war.
The regiment was first assembled at the Presidio, San Francisco, and on the completion of its organization, five companies were sent to Oregon and Washington Territory, to relieve the regular troops ordered east, and two were sent to Santa Barbara. In the summer of 1862, the companies sent to Oregon were returned to California.
At the beginning of 1862, Col. Lippitt was placed in command of the Humboldt Military District, and the 2nd served in this district, on outpost and scouting duty against Indians. In the summer of 1863 a portion of the regiment, including the headquarters, was ordered to Benicia barracks, whence it was ordered to Fort Miller, Fresno county, in Aug., 1863, and served by detachments at various posts in California until October, 1864, when it was ordered to the Presidio, San Francisco.
Here the original members, not reenlisted were mustered out on the expiration of their term of service, and the regiment, composed of veterans and recruits, continued in service.
In Aug., 1865, it was ordered to Arizona, and during the remainder of its term of service occupied stations as follows: Camp on San Pedro river, Fort Grant, and Fort Goodwin, A. T., and Drum barracks, Fort Gaston, Fort Humboldt, and Fort Yuma, Cal.
It was mustered out at the Presidio, San Francisco, April 16 to June 30, 1866.
Source: The Union Army, vol. 4, p. 411
Fought on 28 Jul 1862 at Humbolt County, CA.
Fought on 21 Mar 1863 at Eel River, CA.
Fought on 30 Apr 1863 at Fort Anderson, CA.
Fought on 15 May 1864.