June 11, 1861
Company D, Second Regiment, was mustered into U.S. service and credited to the three-year quota.
The evidence
“Company D, Second Regiment, was raised in the city of Janesville — the first company of volunteers enlisted for the war in Rock County. The company was enlisted under the call for three months, but when mustered into service on June 11, 1861, was credited to the quota for three years. It left Janesville for Madison on the 6th of May, where it was quartered in Camp Randall.”
1879-history-of-rock-county/12-rock-county-ch06-politics-war-record.md, PDF p. 454
Butterfield, C. W., et al. The History of Rock County, Wisconsin: its early settlement, growth, development, resources, etc. Chicago: Western Historical Company, 1879. Cornell University Library via the Internet Archive, archive.org/details/cu31924028871585.
Grade A: Found on a page of one of our sources
On the printed page (PDF p. 454) · open the whole page “Rock county. The company was enlisted under the call for three months, but when mustered into service on June 11, 1861, was credited to the quota for three years. It left Janesville on May 6 for Madison, where it was quartered in Camp Randall.”
1908-brown-rock-county/16-military-history.md, Vol. 1, PDF p. 359 / book p. 330
Brown, William Fiske, editor. Rock County, Wisconsin: A New History of Its Cities, Villages, Towns, Citizens and Varied Interests, from the Earliest Times, Up to Date. Chicago: C. F. Cooper & Co., 1908. 2 vols. archive.org/details/rockcountywiscon01brow, archive.org/details/rockcountywiscon02brow.
Grade A: Found on a page of one of our sources · may repeat 1879-history-of-rock-county, so not counted as independent
On the printed page (Vol. 1, PDF p. 359 / book p. 330) · open the whole page