The Fifteenth was soon after directed to take a position on the extreme right of the First Brigade, and commenced moving to a point on the right of the city; and,  at that same moment, the enemy’s batteries opened from three different points with solid shot and shell, which they kept up while the regiment was going the distance of half a mile. At  the same time this movement was going on, the enemy was hurrying up their infantry at double quick, and filling the rifle pits on the crest of the hill in our front, almost in rifle range.  

It was our good fortune to have a slight embankment for a cover, where we remained for two hours, until the position known as “Mary’s Heights,” in rear of the famous bank-wall rifle pit, where so many of our brave men laid down their lives at the first battle of Fredericksburg, was flanked by Gen. Sedgwick’s Sixth Corps, and the enemy in our front began to fall back.  A canal, some thirty feet wide and two deep to ford prevented our advancing directly on front, and we were obliged to return to the city before doing so.  

During the time we had remained there, the enemy had placed two guns in such a position on the bluff, on the south side of the river, that they had an enfilading fire on our line while returning to the city; but through their great haste to join their fleeing comrades, or bad practice, they did us little harm., but two men slightly wounded during the whole shelling.  

After following up the enemy two miles, the Second division was ordered back to the city, the Fifteenth on the north bank of the river, supporting battery “A,” first Rhode Island Artillery, which covered the pontoon bridge, where we remained until the following day about dusk,  when companies “A,” “B,” “E,” and “G,” moved into the rifle pits, above and below the bridge, to cover its removal.  (MA AG 1863, p. 626-637)

The day was excessively hot, and the roads dusty, and a great portion of the way leading through valleys shut out from air and terribly exposed to the hot rays of the sun, which told fearfully on the men.  Halted about 6, P. M., for the night; having made the distance of eighteen mile.   (MA AG 1863, p. 626-637)

Moved about 3 o’clock, A. M., passing Dumfries at 8, and arrived at the Occoquan River about sunset, being another sultry and tedious day.  Bivouacked for the night.   Moved, the 17^th, at 8 o’clock and arrived at Sangster’s Station, on the Orange and Alexandria   Railroad, at 2 o’clock, P. M.  Here the regiment went into camp, and remained until Friday, the 19^th.  Marched, at half past 12, P. M., for Centerville , five miles distant, where it arrived at dark.   (MA AG 1863, p. 626-637)

The regiment moved to Thoroughfare Gap, a distance of eighteen miles, arriving there about midnight, after a tedious march.  It remained there until the 25^th.  Our forces moved towards the Upper Potomac .  The right wing of the regiment was deployed as flankers, covering the line of march, which, for a considerable distance, was harassed  by the enemy’s cavalry and artillery.  One man of the regiment was wounded.  The bivouac this night was at Gum Springs, fifteen miles from Thoroughfare Gap.  A heavy rain rendered the marching very tiresome.  (MA AG 1863, p. 626-637)

The regiment marched to Edward’s Ferry, where, after many wearisome halts, it crossed the Potomac , bivouacking about midnight, on the Maryland bank of the river.  Distance marched about ten miles.  (MA AG 1863, p. 626-637)

Marched about 3, P. M. Bivouacked at  11 P. M., near Sugar Loaf Mountain , after marching a distance of twelve miles.  Previous to this march, the following order was read to the regiment: (MA AG 1863, p. 626-637)

Marched to Frederick City , a distance of eighteen miles.   (MA AG 1863, p. 626-637)

Moved at 8, A. M., and bivouacked at 9, P. M. near Uniontown , Md. , after accomplishing a march of thirty three miles.  The men were much prostrated by this terrible tax upon their endurance.  (MA AG 1863, p. 626-637)

Regiment starts for Taneytown finally camping for the evening southeast of the Roundtop, 3 miles from Gettysburg." ( 17 miles )"

Started at 8, A. M., and marched to Taneytown.  About noon, heavy cannonading was heard to the northward.  The troops were at once put in motion, and marched rapidly towards the Pennsylvania line, under stringent orders to allow no man, for any cause, to fall behind.  Bivouacked at night behind a barricade of rails, three miles south of Gettysburg ; distance marched this day, seventeen miles.  (MA AG 1863, p. 626-637)

The Fifteenth  with another regiment of the brigade , was now moved out to position full three hundred yards in front of the main line; here,  a barricade of rails was hastily thrown up.  About sunset, the enemy made a furious assault upon our lines.  Having driven the Third Corps they speedily gained the flank of the advanced detachment of  the Second.  

The batteries on the ridge opened on their advance with grape and case shot; but through some deplorable mistake, most of the shots fell short and tore with destructive effect through the ranks of the Fifteenth.  Exposed thus to a fire in front, flank, and rear, the regiment was forced after considerable loss, to fall back to the position behind the ridge.  The regiment bivouacked on the battlefield.   (MA AG 1863, p. 626-637)

Friday - The rebels opened on our lines with over a hundred pieces of artillery, at about 1, P. M.  This terrible fire was continued for over two hours; but though the air seemed filled with fragments of bursting shells, but comparatively little damage was done.  At 3 P. M., the rebel infantry moved to the assault.  Our men sprang promptly to meet them, glad at the prospect of work, relieving them from their painful recumbent position, which a boiling sun rendered the more intolerable.  this contest lasted an hour or two; during which both armies showed a determination to hold its ground, regardless of the results.  A slight wavering  of the rebel line was detected, and at the suggestion of Colonel Hall commanding Third Brigade, the colors of the Fifteenth were ordered to advance, when the remnant of the regiment rallied promptly around them, and the whole line, as if moved by one impulse, rushed  forward, and carried the position. 

The regiment was sent out to picket the field; and at daylight on the morning of the 4^th, skirmishing commenced, and continued until the regiment was relieved, at 8 o’clock.  the regiment went into action with 18 officer and 224 enlisted men.  during the three days, it lost 3 officers (Colonel Ward and captains Murkland and Jorgensen) killed, and 8 officers wounded, and 19 enlisted men killed and 85 wounded, many of whom have since died.  Saturday, July 4^th, was spent on the field.  (MA AG 1863, p. 626-637)

At 2, P. M. Sunday, July 5^th, the regiment left the battle ground, and marched to “Two Taverns,” a distance of six miles, where it remained until the morning of the 7^th, when it moved five miles farther to Taneytown.  Leaving Taneytown on the eighth, in a pouring rain the march was continued over horrible roads, through Woodsborough to the neighborhood of Frederick City , a distance of eighteen miles.  On this march the dispatch announcing the capture of Vicksburg was published to the troops, and received with greatest enthusiasm.  (MA AG 1863, p. 626-637)

The march was resumed at an early hour; crossed South Mountain at Crampton’s Gap.  bivouacked at 9, P. M. Distance marched of eight miles.  July 11, moved three or four miles to a point near Hagerstown .  (MA AG 1863, p. 626-637)

Major George C. Joslin writes the official after-action report of the 15th MVI at Gettysburg.

The regiment took its position in the line of the Second corps in front of the enemy, and built a strong breastwork of earth and logs behind which it lay until the morning of the 14^th, when the enemy having retreated across the river, our forces moved up and occupied Williamsport .  On the 15^th, the regiment  marched to Sharpsburg , and from thence by the “Tow Path” to the vicinity of Sandy Hook , a distance of seventeen miles.  (MA AG 1863, p. 626-637)

Moved about five miles to Pleasant Valley, and camped until the 18^th, when crossing the Potomac and Shenandoah Rivers at Harpers Ferry, the line of march was taken up down Loudon Valley over the same ground traveled in the fall campaign of the previous year.  Distance marched this day, ten miles.  (MA AG 1863, p. 626-637)

Moved about eight miles to the vicinity of Snicker’s Gap.  (MA AG 1863, p. 626-637)

Moved six miles to Bloomfield , at which place a halt was made until the 22d, when the march was continued to Ashby’s Gap, a distance of eleven miles.   (MA AG 1863, p. 626-637)

Moved to Markham Station on the Manassas Gap Railroad; here a halt of some hours was made.  Meantime, a portion of the Third Corps having become engaged with the enemy at Manassas Gap, the Second Corp was started to their assistance.  Hurrying as fast as possible over paths frightfully rough, it reached the scene of the conflict about midnight, when the exhausted men were allowed to make coffee, and bivouac for the remainder of the night.  Distance marched this day, seventeen miles.  (MA AG 1863, p. 626-637)

The rebels having retreated, our forces began to move out of the Gap.  The Fifteenth bivouacked at Markham Station, five miles back.   (MA AG 1863, p. 626-637)

Marched to White Plains , a distance of twenty miles, and continued the march on the 26^th, via Warrenton to the Junction, a distance of twenty-three miles, went into camp near the latter place.  Here the regiment remained until the 30^th.  Tents were struck at six o’clock P. M., and the corps moved toward Morrisville; being the rear guard of the trains, our movements were necessarily very slow, making but five miles before two o’clock, A.M., of the 31^st.  Bivouacked by the roadside until morning.  Moved again about 9 A. M., and reached Morrisville at 5, P. M., and encamped in woods; weather very hot.  (MA AG 1863, p. 626-637)

The regiment with the rest of the  Second division went to Bank’s Ford, arriving there about sunset; distance marched, twenty miles.  remained at this point until September 3d, when the object of the movement having been successfully accomplished, namely, the destruction of the gunboats, we took up the line of march for our camp at Morrisville, at half-past six o’clock, P. M., which place was reached at two o’clock, A. M., of September 4^th.  (MA AG 1863, p. 626-637)

The regiment broke camp at 10 o’clock, A. M., and with the rest of the Second Corps, marched to Bealton station and bivouacked near the railroad.  (MA AG 1863, p. 626-637)

Very rainy in forenoon.  The regiment moved at & A. M., and crossed the Rappahannock at Rappahannock Station, the Second Corps being a support to the cavalry, which was advancing toward Culpepper Court House, which place we reached at 4 o’clock P. M.  

Remained here until the 16^th, when the regiment moved out through the town one mile and a half in a westerly direction, and was directed to go into camp; all the while rapid Cannonading was distinctly heard towards Raccoon Ford on the Rapidan River.  The men has scarcely got their tents pitched, when orders came to be ready to move at a moments notice.  Every man laid himself down that night with a feeling that he would be called upon to meet the enemy on the anniversary of the bloody battle of Antietam .  (MA AG 1863, p. 626-637)

Orders came to move at 5 o’clock, A. M., when the regiment moved towards Raccoon Ford, where it arrived about noon.  The Second Corps relieved the cavalry, and picketed along the river from the ford to Cedar Mountain , this regiment being situated opposite Robinson’s ford.  For several days, the enemy kept up a constant fire on our pickets, whenever exposed to view, themselves being concealed among the scrub-oaks on the bluff on the south side of the river.  They seemed to take the occasion of our relieving pickets to fire upon us, which compelled our men to deploy and reach their position at the double quick.  (MA AG 1863, p. 626-637)

Orders were received  about noon to strike tents immediately, and the regiment had scarcely got packed up, when the bugle sounded the “assembly”; lines were formed and marched out some four miles west of the ground occupied, and formed a line of battle along a piece of woods, stacked arms, and bivouacked in rear of the stacks.  (MA AG 1863, p. 626-637)

Turned out at half past one A. M. , and moved at 2 o’clock via Brandy Station to Rappahannock Station recrossed the river about noon, and moved out one mile north of Bealton Station.  (MA AG 1863, p. 626-637)

The regiment received orders at one  o’clock, P. M. , to move immediately.  Proceeded back to Rappahannock Station and again crossed the river, and moved in line of battle to within some two miles of Brandy Station.  Halted at sunset and bivouacked.  At 12 o’clock, (midnight) the regiment received orders to turn out and move at once.  

Again marched back to Rappahannock Station and recrossed the river, and took up a line of march via Bealton Station towards Sulphur Springs, where our cavalry had been repulsed the day previous by the enemy’s infantry.  Arrived within about two miles of that place, at 7 o’clock, A. M., when the Second Corps was massed by divisions, stacked arms and rested till about noon, when the regiment together with the rest of the corps moved toward Warrenton Junction, which place was reached about dark, and bivouacked for the night, to enable the baggage trains to get well out of the way, that they might not interfere with the march of he troops.   (MA AG 1863, p. 626-637)

Moved at 5 o’clock, A. M., for Manassas Junction.  While passing near Auburn , the enemy attacked the Third Division of the Second Corps; still the column pressed on, this regiment  as flankers for the First Brigade, until it reached Catlett’s Station.   Here a halt was made for coffee, and the column moved on, the cavalry skirmishing with the enemy in the rear.  

When near Bristow Station the head of the column, (this regiment being second in line,) was attacked by the enemy’s infantry and artillery, and our line of battle formed under a sharp fire, along the embankment of the railroad, and was hotly engaged for about an hour, repulsing the enemy with heavy loss to them, and comparatively light to this regiment.  In total loss was one officer, (Lieutenant Charles H. Stevens, ) mortally wounded, (and has since died,) and two enlisted men killed, nine wounded and two missing.  

Remained in this position until 9 o’clock, P. M., when the regiment moved on via Manassas Junction, fording Bull Run at 3 o’clock A. M., of the 15^th; bivouacked on the north bank until daylight, when the regiment moved to the right, to a point one mile and a half from Centerville, and formed line of battle.  The pickets of the regiment were engaged with those of the enemy, for the greater portion of the day, and the regiment exposed to the fire of their batteries, but no casualties occurred.  Toward night tents were pitched, and the men directed to make themselves as comfortable as possible.  (MA AG 1863, p. 626-637)

The regiment moved at 7 o’clock, A. M. , via Manassas Junction, and halted about 2, P. M.,  1 ½ miles north of Bristow station, and bivouacked for the night.  Marched at 6, A. M.., October  20^th, towards Gainesville , fording “Broad Run” at two different points, and later in the day, “Muddy Run” and “Kettle Run.”  Reached Auburn at sunset, and bivouacked in the woods, near the point where a part of Second Corps was attacked on the 14^th.  

The regiment pitched tents the day following, and remained here until the 23d.  Marched at 7, A. M. to within two miles of Warrenton, and went into camp along  the Warrenton Branch Railroad.  here the men commenced building log-houses, and, in some cases completed them, but were allowed to enjoy them but a short time; for, on the 7^th of November, the regiment moved at 5 o’clock, A. M. via Warrenton Junction and Bealton, to “Kelly’s Ford,” on the Rappahannock.  Bivouacked at dark half mile from the river.  

This was one of the hardest marches, for the distance, that the regiment has ever experienced.  Many of the men had just drawn clothing, which together with eight days rations and rapid marching over a dusty road, told on their strength severely, although the distance marched was but twenty miles.  (MA AG 1863, p. 626-637)

Turned out at 5 o’clock, A. M., and crossed the river on pontoon bridges about sunrise.  The Second Division advanced in line of battle, by brigade, (this regiment being in the second line) about one mile, then moved in a westerly direction some three miles, halting at intervals, while our skirmishers were advancing slowly.  At 4 o’clock, P. M., pitched tents, and remained here until the 10^th, when the regiment moved some 2 ½ miles west, and occupied the partially built barracks of the “Stonewall” Brigade of the rebel  General Picket’s division.  

This camp was known as “Camp near Brandy Station.”   Remained here till  November 24^th.  Orders came the night previous, to march at 5, A. M.  The regiment moved at that hour, and soon after, it commenced raining.  When about two miles out, it rained in torrents; and the troops were ordered back to camp.  (MA AG 1863, p. 626-637)

Marching orders were again received, and the regiment moved at 6 o’clock, A. M., and proceeded to “Germania Ford,” on the Rapidan River .  Crossed on pontoon bridge at 4 o’clock P. M., and bivouacked two miles from the south bank.    (MA AG 1863, p. 626-637)

Turned out at 5 o’clock, A. M. and marched at sunrise; making a rapid march to “Robertson’s Tavern,” a distance of six miles, where the second Brigade of our division was already skirmishing with the enemy.  Almost immediately, this regiment was deployed as skirmishers, joining on the right of the Second brigade. The regiment exchanged but few shots with the enemy for some two hours, when the order came to advance our line, and in so doing, the right and center became briskly engaged, the enemy at once throwing forward a line of battle which compelled it to retire to its original position, where, with the help of our supports, we held them in check and finally drove them back.  In this skirmish, the regiment lost two officers wounded, 1 mortally, and 1 missing (Lieutenant Colonel Joslin,) taken prisoner; 9 enlisted men were wounded, and 6 enlisted men missing.  

The regiment was again ordered to advance about sunset, supported by a line of battle, to open the road by which General French, of the Third Corps, was expected to arrive; in doing which it received two volleys from the enemy, but owing to the nature of the ground, their shots went harmlessly over our heads, and we gained the desired position, where we remained until half-past 9 o’clock, P. M., when the regiment was relieved, and bivouacked in the second line of battle.   (MA AG 1863, p. 626-637)

Crossed the pontoon bridge; halted to make coffee at 11, A. M.., and moved again at 1, P. M. and reached our old camp near Brandy Station at 9 o’clock P. M., having been twenty-four hours on the march.  (MA AG 1863, p. 626-637)

The regiment moved to a position one mile south of Stevensburg.  (MA AG 1863, p. 626-637)