Not trying to hog the subject but it deeper than many suspect. On the early, what we know now as, Louisiana/Arkansas/Texas frontier, a man of any means was mounted with single shot pistols and a sabre. The cutting commenced as soon as the brace or three of pistols were discharged.
With the rise of settlements and towns, a shorter sabre was required for the dismounted man, and gave rise to the bowie which likely already was not uncommon and Jim Bowie one of many owners of such, although he also had his own specifications as did any owner approaching a smith.
But it maintained sabre characteristics for sabre tactics of land owners already well versed in same. Generous handle for extention on thrust, curve to spine and belly, and long swept hook clip for the nearly indefensible back cut, so superior that it was treated much as assault rifles today, thanks to southern tendency to duel/robbers armed with same/lurid press back east both true and false, and banned by national congress circa 1830 and not lifted until early 1950s, still illegal or regulated to some degree in most states until today, even if nobody remembers the reason for the ban. Guards initially of sabre type and then trimmed for daily concealment under the outer great coat when about town.
Same as with the sabre, there were various schools teaching the art of fighting with same, and one need only look at Von Tempsky of European training and legendary transition to bowie in California and prowess with same there, as well as Mexico, Central America, and in the Maori wars in New Zealand. A former trooper under his command was interviewed in 1900 ("old Von was a terror with his bowie"), and still possessed his broken and retipped knife which Von Tempsky provided his cadre, and described as still nearly a bayonet (bayonets of that era and British make being quite long)....no heavy cleaver would fit that description, although the knives were reputed to be circa 1/4" thick.
Obviously, the bowie made by Bo Randall is very close to such a knife and was noted so by Raymond Thorpe. The Bagwell, in addition, has the curved sabre down/up belly and spine from guard to tip design. Other features not immediately apparent would be the hand-specific handle (biased, actually, and still works great in opposite), which is more straight back from spine on top with a slight flair at rear, while curving down and deepening on the bottom, reinforced tip of knife dropped to centerline, handle designed for retention as well as heel of hand to pommel for increased reach in thrusts, while flats prevent twisting.
Of the "bowie" knives out there, the Thorpe and Bagwell seem to me to be as close as one might get.
PS- a true blade artist of the time, or any time, would also have had a dagger or toothpick in weak hand to guard the weak side, but that is a totally different story except in regards also to such knives being offered nowadays being also proper and correct, and not just a hollywood thing.
PPS-1842 NYC even