First organized as the 4th Texas Cavalry Battalion or Whitfield's Legion, the unit served dismounted at Pea Ridge and First Corinth.

[4][note 1] McIntosh told his cavalry regiment commanders to wait for orders and impulsively moved forward to get the infantry attack rolling.

At about 3:30 pm, Albert Pike assumed command of McCulloch's division and led about 2,000 troops, including Whitfield's Legion, to join the rest of Earl Van Dorn's army which was east of Pea Ridge.

[10] Around mid-morning, Van Dorn found that his ordnance train was miles away; without the ability to get additional ammunition, he was forced to order a retreat.

His troops marched from Van Buren, through Little Rock to Des Arc, Arkansas, where they boarded steamboats bound for Memphis, Tennessee.

[15] At the Battle of Iuka on 19 September 1862, the 1st Texas Legion (dismounted) was assigned to Hébert's 2nd Brigade, Lewis Henry Little's 1st Division, Price's Army of the West.

[23] A Federal attack briefly pushed the 1st Texas Legion off the ridge, but the Texans retook it, and with darkness the fighting finally sputtered out.

[24] At the Second Battle of Corinth on 3–4 October 1862, the 1st Texas Legion (dismounted) was part of W. Bruce Colbert's brigade, Hébert's division, Sterling Price's corps.

When a Union army under Ulysses S. Grant invaded Mississippi from the north, the Confederates attempted to strike at its Holly Springs supply base.

[35] The Holly Springs Raid was a huge success on 20 December when Van Dorn's troopers captured 1,500 Union soldiers and put Grant's supplies to the torch.

Whitfield received promotion to brigadier general in May 1863,[35] with Hawkins replacing him as colonel of the 27th Texas Cavalry until the end of the war.

On 5 March 1864, a brigade of Tennessee cavalry under Robert V. Richardson joined Ross' troops in an attack on the Federals in the Battle of Yazoo City.

[40] A few days later, Ross reported that Union forces under the overall command of William T. Sherman crossed the Etowah River at Wooley's bridge west of Kingston.

[42] Soon after the Battle of Kennesaw Mountain on 27 June, a Union infantry division drove Ross' Brigade from the point where the Sandtown Road crossed Olley's Creek and gained a foothold.

[43] On 29 July, Edward M. McCook's Union cavalry division raided behind Confederate lines, burning 500 wagons and damaging the railroad at Lovejoy's Station.

Because Joseph Wheeler took 6,000 Confederate cavalry to raid Sherman's railroad supply line, only 400 horsemen under Ross were immediately available to oppose the Union raiders.

Though the new Confederate army commander John Bell Hood sent reinforcements, they went astray, so that the Union raiders chased Ross out of Jonesborough.

After marching to Lovejoy's Station on 20 August, Kilpatrick's cavalry got caught between a cavalry-infantry force in front and Ross' Brigade in their rear.

In the only successful saber charge during the campaign, the Union raiders simply galloped through Ross' outnumbered troopers, capturing a howitzer and the colors of the 3rd Texas Cavalry.

On 30 August 1864 near Jonesboro, major Union units forced a crossing of the Flint River against the opposition of the cavalry brigades of Ross and Frank Crawford Armstrong.

[47] That day, two Union corps occupied a section of the railroad near Rough and Ready, essentially dooming the Confederate defense of Atlanta.

Later that morning, faced with solid columns of retreating Federal infantry, Ross' Brigade was unable to attack the Union wagon train.

Ross' Brigade crossed the Harpeth River at Hughes Ford but soon ran into superior numbers of Federal cavalry and was compelled to fall back.

[53] The 27th Texas Cavalry missed the Battle of Nashville because Hood ordered Forrest to take the divisions of Jackson and Abraham Buford to Murfreesboro.

Hood hoped that by harassing its 8,000-man Federal garrison, he would compel the Union army of George H. Thomas at Nashville to commit a blunder.

In the event, the Confederate infantry ran away so quickly that the Union force captured two guns and 207 men before Jackson's horsemen could intervene.

The next day, Forrest again set an ambush at Sugar Creek, with Confederate infantry deployed in the center and the cavalry of Ross and Armstrong on the flanks.