This Regiment, composed substantially of Germans, was raised chiefly at Toledo, Cleveland and Chillicothe, being the third German Regiment from Ohio. Its organization was commenced under the second call of President Lincoln for 300,000 men, August, 1861. So prompt was the movement that the Regiment was mustered into the service October 2d, fully prepared for the field. For Colonel, Edward Siber, a skilled and competent officer of the German Army, who had served in Prussia and Brazil, was appointed, with Louis von Blessingh, of Toledo, as Lieutenant-Colonel, and Charles Aubele, of Cleveland, as Major. The line officers were chosen from those who had been in the three-months' service.

The Regiment moved from Camp Dennison to a point on the Kanawha River, West Virginia, reporting to General Rosecrans. It was soon sent, with other forces, up the Kanawha, to the Oil Works at Cannelton, for the purpose of driving Floyd's Rebel force out of the valley, which object was accomplished, the enemy being driven to within seven miles of Raleigh C.H. Returning, the Regiment went into winter quarters at Clifton, where, besides drilling, it was employed in more or less occasional service in the protection of important points in that section. In January, 1862, it was sent to Logan C.H., East of Guayandotte River, when, after a hard march of 80 miles, and much brisk skirmishing, the place was captured, and all war material destroyed, when the Regiment returned to Clifton, with loss of one officer and one man killed.

In March, 1862, the Thirty-Seventh Ohio was attached to the Third Provisional Brigade of the Kanawha Division, which was sent on a raid to the southern part of West Virginia, for the destruction of the Virginia and East Tennessee Railroad, near Wytheville. This expedition was not successful. The Regiment lost one officer and 13 men killed, 2 officers and 46 men wounded, and 14 men missing. The force proceeded to Flat-Top Mountain, where it remained until August 1st, when it marched to Raleigh to garrison the place and do scouting service for a circuit of 25 miles. The latter part of August it moved in detachments to Fayetteville, Virginia, and, with the Thirty-Fourth Ohio, it garrisoned that place. In September the whole force engaged with General Loring's Rebel command, and after fighting from 12 M. until dark, the approach of Rebel re-enforcements made a retreat necessary to Cotton Hill, on the Gauley Road, where the enemy were fought successfully for an hour. The Union troops continued their retreat, arriving at Charleston September 13th, where they stopped for the protection of a valuable train of 700 wagons, with supplies for all troops in the Kanawha Valley. September 15th the Ohio River, opposite Ripley, Ohio, was reached, where they crossed, but almost immediately recrossed, and went into camp at Mt. Pleasant. In the unfortunate retreat the Regiment lost 2 men killed, 3 wounded, and 62 missing, while all the Company wagons, camp equipage and officers' baggage were lost near Fayetteville by a rear attack of the enemy.

October 15, 1862, the Regiment, under Lieutenant-Colonel von Blessingh, advanced up the Kanawha Valley, reaching Gauley Bridge November 20th, whence, December 30th, it marched to Camp Piatt and embarked by steamers for Cincinnati. Colonel Siber joined his command at the latter point, and the Soldiers exchanged their arms for Enfield rifles. From Cincinnati the Regiment proceeded down the river, landing first at Napoleon, Arkansas, January 16, 1863, where it was attached to the Third Brigade, Second Division, of the Fifteenth Army Corps. On the 21st this force moved to Milliken's Bend, nearly opposite Vicksburg, where it was employed on the canal for isolating that Town from the Mississippi, but a freshet soon drove them to higher ground at Young's Point, whence various expeditions were sent out in different directions.

April 29, 1863, the Regiment, under Lieutenant-Colonel von Blessingh, with eight other Regiments, took steamers for Haines's Bluff, up the Yazoo River, for the purpose of a feint, to cover General Grant's plans below Vicksburg, but soon returned to Young's Point, where it was on guard and fatigue duty until May 13th, when it went down to Grand Gulf. From this point it marched with other troops, under Grant, to the rear of Vicksburg, and was assigned as a portion of the front line of the force investing that place. In the severe but unsuccessful assaults on the Rebel works, on May 19th and 22d, and the following siege, the Regiment lost 19 killed and 75 wounded, the latter including Lieutenant-Colonel von Blessingh, whereby the command of the Regiment was devolved upon Major Charles Hipp, until June 18th, when Colonel Siber resumed command.

After the surrender of Vicksburg the Thirty-Seventh participated in the expedition against Jackson, Mississippi, where it did provost guard duty. July 23d it marched to Camp Sherman, near Big Black River, remaining there until September 26, 1863, when it marched to Vicksburg and took steamer for Memphis; thence marched to Corinth, to Cherokee Station, Alabama, where it remained in bivouac until October 26th. With its Division the Regiment marched to drive off Forrest's Rebel Cavalry from their interference with the Union forces operating for the relief of Chattanooga, which point was reached November 21st. On the morning of the 25th the Regiment took part in an assault on the enemy's fortified position, losing S men killed and 36 wounded. The enemy retreated the following night, and were followed as far as Ringgold. November 29th the Regiment started on a three weeks' expedition to East Tennessee, to drive out Longstreet's Rebel force, which movement involved intense suffering by the troops, in consequence of the severity of the cold, and a want of clothing and of rations; many Soldiers were shoeless; yet they endured such trials not only without a murmur, but throughout showed unusually exuberant spirits. Returning to Bridgeport, Alabama, the Regiment remained there until December 26th, and then went into camp at Larkinsville, Alabama. Early in February, 1864, the Thirty-Seventh formed part of an expedition toward Lebanon, Alabama, marching with the Fifteenth Army Corps on a reconnaissance near to Dalton, and returning to Larkinsville March 2d.

March 8, 1864, three-fourths of the men of the Regiment re-enlisted for another three years' term, and were placed in the Second Brigade, Second Division, Fifteenth Corps. The usual thirty days' leave was spent by the men in a visit to their homes in Ohio, when they rendezvoused at Camp Taylor, near Cleveland. Leaving that place, they were again at the front April 28th. On their passage, 30 men were wounded and one killed by a railroad accident near Munfordsville, Kentucky. Reaching Chattanooga, the Regiment joined its Division May 10th, in Sugar Creek Valley, Georgia. On the 13th it lost 3 men killed (2 being officers) and 10 wounded. Thence it marched to Kingston, Georgia, reaching there 19th. It was then under command of Major Hipp, the Lieutenant Colonel being in Ohio, on sick leave. In the march on Atlanta the Regiment lost four men wounded at Dallas and New Hope Church. On the retreat of the enemy the Thirty-Seventh pursued toward Acworth, and participated in the memorable but disastrous assaults made against the Rebel stronghold on Kenesaw Mountain, which the enemy were compelled to abandon. June 11th to July 2d the Regiment lost 4 men killed and 19 wounded.

The next movement of the Regiment, with its Division, was to the extreme right of the Army, supporting the Twenty-Third Army Corps in the engagements near the Chattahoochie River and Nicojack Creek. July 12th it moved, passing through Marietta, Rosswell Factories, and across the Chattahoochie River, and destroyed the Atlanta & Augusta Railroad for a considerable distance; whence it marched through Decatur, and encamped, July 20, 1864, near Atlanta. On the 22d the Regiment was on the right of the Division, in breastworks abandoned by the enemy; but by re-enforcements of the Rebels the Union lines were broken, and the Thirty-Seventh compelled to evacuate, losing 4 men killed, 10 wounded and 38 taken prisoners. By most desperate effort the Union troops, with the help of the Sixteenth Army Corps, re-took the position and held it. July 27th the Fifteenth Corps moved to the right of the besieging Army, thus threatening the enemy's communications with the South, to prevent which they made an effort to drive the Union forces from their position, when the battle of Ezra Chapel was fought, in which the Rebels were severely punished. In this engagement the Thirty-Seventh held the extreme right, deploying as skirmishers, and frustrated the enemy's attempt to turn the Union right. In this movement Major Hipp lost his left arm, devolving the command upon Captain Morritz. The Regiment lost one man killed and five wounded.

From July 28th to August 26th was consumed in the advance of the Union lines toward the fortifications in front of the railroad between Atlanta and East Point, in which the Regiment lost five men killed and eight wounded. The 30th August found it in line of battle moving on Jonesboro, in advance of the Brigade. In the bloody repulse of the enemy s charges and other movements it lost in two days two killed and seven wounded. The night of September 1, 1864, found the Union forces in possession of Jonesboro and Atlanta, and in a pursuit of the Rebel Army, which ended at Lovejoy's Station. The Regiment returned to East Point September 7th, and rested in camp until October 4th, when it left in pursuit of Hood's forces. Forced marches were made over Northern Georgia and Alabama, and returned to Ruffin's Station, near the Chattahoochie, where it remained until November 13th. At this point Lieutenant-Colonel von Blessingh resumed command of the Regiment, relieving Captain G. Boehm, who had taken the place of Captain Morritz, absent on leave.

November 13, 1864, the Thirty-Seventh Ohio entered Atlanta to draw the outfit necessary to the "March to the Sea," which began on the 15th. Throughout that long journey the Regiment did active and full duty in the various kinds of service from time to time assigned to it. At Clinton, in company with the Fifteenth Michigan, it did valuable service in preventing Rebel Cavalry from crossing the road leading to Marion, with the view of capturing a Division train. Arrived at Savannah, the Regiment occupied itself in drilling, perfecting its equipment and fortifying. January 19, 1865, it marched to Fort Thunderbolt, on the Savannah River, and there embarked for Beaufort, South Carolina, arriving there on the 22d, where it went into camp, but soon returned to Beaufort, and on the 30th started for the march through South Carolina, and the Southern part of North Carolina. bivouacking near Columbia. Again moving, February 18th, it was engaged in destroying the track of the Columbia & Charleston Railroad. By March 7th Cheraw was reached, and the Great Pedee crossed, and subsequently the Regiment was ordered to escort General O.O. Howard's headquarters and pontoon train of the Army of the Tennessee (right wing), which it brought safely into Fayetteville, North Carolina, March 11th. On the 24th it reached Goldsboro, where it was in camp until the capitulation of Lee and Johnson, when, with the rest of the Union troops, it proceeded to Washington, and thence by rail to Louisville, where it lay until the latter part of June, when, with the Second Division, Fifteenth Corps, it went to Little Rock, Arkansas, arriving July 4th. Here, August 12th, it was mustered out, and proceeded to Cleveland, Ohio, and was discharged, the men returning to their homes.