First Battalion Massachusetts Heavy Artillery.
（1) Maj. Stephen Cabot
（2) Maj. John W. M. Appleton
|Field and staff.||Line.||A||B||C||D||E||F||Unassigned Recruits.||Totals.|
|Number on regimental rolls,—|
|Enlisted men (included above) commissioned in regiment.||–||–||8||1||2||1||–||–||–||12|
|Enlisted men (included above) serving elsewhere within regiment.||–||–||–||–||–||–||–||–||–||–|
|Actual total of members of regiment,—|
Co. A, formed early in 1862, was the first company raised of those which formed at a later date the 1st Battalion Mass. Heavy Artillery.
It was organized for the purpose of garrisoning the forts in Boston harbor
. Co. B.
was organized in the autumn of 1862, and both these companies were stationed at Fort Warren
, Boston harbor
, serving there on garrison duty as the 1st and 2d Cos. Heavy Artillery until the spring of 1863.
In April, 1863, these companies, with the 4th Unattached Co. Heavy Artillery, mustered April 22, were united to form the 1st Battalion Heavy Artillery.
The organization was enlarged by the addition of the 5th Unattached Co. in June, 1863, forming Co. D, and by Cos. E and F, added in August, 1864.
The battalion was on garrison duty at the forts in Boston harbor
throughout its term of service, providing, by detachments, garrisons for many forts along the Massachusetts coast
. Three companies were mustered out in June, 1865, and the remainder in September and October of the same year.