One of the most influential accounts of the battle of Cowpens is British commander Lieutenant-Colonel Banastre Tarleton's memoirs, published 6 years after the battle. His description is largely consistent with Cornwallis' report, but provides a great deal of additional detail. Whereas Cornwallis differed from Morgan on only a few points (which side had the numerical advantage, how many British casualties were incurred, and when the 71st Foot was added to the fight), Tarleton's account adds additional differences (how the British were deployed during the battle, the timing of a charge by the British cavalry, and the number of American casualties). Interestingly, his description of when the 71st joined the battle is closer to Morgan's report than to Cornwallis.
Tarleton's history includes some demonstrably false statements, including, for example, that "the number of the killed and wounded... amounted to near three hundred on both sides." His account was also clearly written so as to burnish his reputation (e.g., "the disposition was planned with coolness, and executed without embarrassment"). The defeat resulted from "the bravery or good conduct of the Americans, ...the loose manner of forming which had always been practised by the King's troops in America; or ...some unforeseen event, which may throw terror into the most disciplined soldiers, or counteract the best-concerted designs." He also believed that a lack of support from Cornwallis helped turn defeat into disaster.
Tarleton's critic, Lieutenant Rodericak Mackenzie of the 71st Foot, later argued that none of these excuses were adequate and firmly pinned the blame for defeat on Tarleton himself.
The lateness of Tarleton's account, the questionable statements included in it and the questionable motives behind it (the narrative was written at a time when he was becoming increasingly involved in politics) might convince one that it is a good deal less veracious than Morgan's after action report. But in fact Tarleton's description of events has sometimes been given precedence over Morgan's in histories of the battle.
A portion of Tarleton's description appears below:
Lieutenant-colonel Tarleton having attained a position, which he certainly might deep advantageous, on account of the vulnerable situation of the enemy, and the supposed vicinity of the two British corps on the east and west of Broad river, did not hesitate to undertake those measures which the instructions of his commanding officer imposed, and his own judgement, under the present appearances, equally recommended. He ordered the legion dragoons to drive in the militia parties who covered the front, that General Morgan's disposition might be conveniently and distinctly inspected. He discovered that the American commander had formed a front line of about one thousand militia, and had composed his second line and reserve of five hundred continental light infantry, one hundred and twenty of Washington's cavalry, and three hundred back woodsmen. This accurate knowledge being obtained, Tarleton desired the British infantry to disencumber themselves of every thing, except their arms and ammunition: The light infantry were then ordered to file to the right till they became equal to the flank of the American front line: The legion infantry were added to their left; and, under the fire of a three-pounder, this part of the British troops was instructed to advance within three hundred yards of the enemy. This situation being acquired, the 7th regiment was commanded to form upon the left of the legion infantry, and the other three-pounder was given to the right division of the 7th: A captain, with fifty dragoons, was placed on each flank of the corps, who formed the British front line, to protect their own, and threaten the flanks of the enemy: The 1st battalion of the 71st was desired to extend a little to the left of the 7th regiment, and to remain one hundred and fifty yards in the rear. This body of infantry, and near two hundred cavalry, composed the reserve. During the execution of these arrangements, the animation of the officers and the alacrity of the soldiers afforded the most promising assurances of success. The disposition being completed, the front line received orders to advance; a fire from some of the recruits of the 7th regiment was suppressed, and the troops moved on in as good a line as troops could move in open files: The militia, after a short contest, were dislodged, and the British approached the continentals. The fire on both sides was well supported, and produced much slaughter: The cavalry on the right were directed to charge the enemy's left: They executed the order with great gallantry, but were drove back by the fire of the reserve, and by a charge of Colonel Washington's cavalry.
As the contest between the British infantry in the front line and the continentals seemed equally balanced, neither retreating, Lieutenant-colonel Tarleton thought the advance of the 71st into line, and a movement of the cavalry in reserve to threaten the enemy's right flank, would put a victorious period to the action. No time was lost in performing this manoeuvre. The 71st were desired to pass the 7th before they gave their fire, and were directed not to entangle their right flank with the left of the other battalion. The cavalry were ordered to incline to the left, and to form a line, which would embrace the whole of the enemy's right flank. Upon the advance of the 71st, all the infantry again moved on: The continentals and back woodsmen gave ground. The British rushed forwards: An order was dispatched to the cavalry to charge: An unexpected fire at this instant from the Americans, who came about as they were retreating, stopped the British, and threw them into confusion. Exertions to make them advance were useless. The part of the cavalry which had not been engaged fell likewise into disorder, and an unaccountable panic extended itself along the whole line. The Americans, who before thought they had lost the action, taking advantage of the present situation, advanced upon the British troops, and augmented their astonishment. A general flight ensued. Tarleton sent directions to his cavalry to form about four hundred yards to the right of the enemy, in order to check them, whilst he endeavoured to rally the infantry to protect the guns. The cavalry did not comply with the order, and the effort to collect the infantry was ineffectual: Neither promises nor threats could gain their attention; they surrendered or dispersed, and abandoned the guns to the artillery men, who defended them for some time with exemplary resolution. In this last stage of defeat Lieutenant-colonel Tarleton made another struggle to bring his cavalry to the charge. The weight of such an attack might yet retrieve the day, the enemy being much broken by their late rapid advance; but all attempts to restore order, recollection, or courage, proved fruitless. Above two hundred dragoons forsook their leader, and left the field of battle. Fourteen officers and forty horsemen were, however, not unmindful of their own reputation, or the situation of their commanding officer. Colonel Washington's cavalry were charged, and driven back into the continental infantry by this handful of brave men. Another party of the Americans, who had seized upon the baggage of the British troops on the road from the late encampment, were dispersed, and this detachment retired towards Broad river unmolested. On the route Tarleton heard with infinite grief and astonishment, that the main army had not advanced beyond Turkey creek: He therefore directed his course to the south east, in order to reach Hamilton's ford, near the mouth of Bullock creek, whence he might communicate with Earl Cornwallis.
The number of the killed and wounded, in the action at the Cowpens, amounted to near three hundred on both sides, officers and men inclusive: This loss was almost equally shared; but the Americans took two pieces of cannon, the colours of the 7th regiment, and near four hundred prisoners.
Copies of Tarleton's and Mackenzie's descriptions of the battle can be found on John Moncure's online history of the battle, The Cowpens Staff Ride and Battlefield Tour, and Marg Baskin's Banastre Tarleton website.