I have not seen this before-let's take who is the best, head to head under neutral rules, by height. Not in terms of relative to their division, I mean if the categories were just by height, under neutral rule sets. So maybe under 5'4". This content is protected 5'6". This content is protected 5' 8". This content is protected 5'10". Let's try to get their likely reakl height. So a Tyson & Frazier would not quite qualify, but Marciano may well. Tua? Only IF he was shorter than his listed 5' 10". As great as a Duran or Hagler would be, it seems unlikely that they would beat the very best of much bulkier guys head to head. Even Greb would be challenged, especially if he is not rules as *under* 5'8". Top contenders would be guys like Barbados Joe Wolcott. Dwight Muhammed Quai. Henry Armstrong. Sam Langford. Then you can take them against each other, also or especially if they are in diffirenet height "divisions". Could Langford, peak at about or just over Quai's peak weight, take him? Who else am I forgetting at the moment?
Under 5’4 will include most lower weight fighters from flyweight down and a fair few above flyweight too. For example, if we’re using Boxrec as a source, Vicente Saldivar was 5’3 and he was a featherweight. Esteban DeJesus was 5’4 and he was a lightweight. Hell, James Hardrock Green is listed as 5’4 and he was a light middleweight and middleweight (not that he was a great fighter).
Pascual Perez was 4ft 11" and Jimmy Wilde was 5ft 2", of course both total legends. Baby Jake Matlala was 4ft 10", not a great but a very decent fighter. Shortest champ ever I think?
You still get bigger height disparities in the HW division. I don't know the best short guy EVER, but guys like Frazier, Monte Barret and a few others come to mind
Tommy Burns under 5’8 would be more than a handful for most in his height range considering his 180lb frame
The under 5'8" would be interesting. Qawi against a bunch of dudes his own height, most of whom weigh a good bit less? Dear god.
Best H2H, relative to the era in which they competed (to eliminate rule set, with/without PEDs, etc. considerations), in a no upper weight limit contest (which is what I think you're asking), off the top of my head,imo: <5ft 10ins = David Tua or Sam Langford (strictly relative to their own era, prime Langford was a better HW than Tua) <5ft 8ins = Sam Langford <5ft 6ins = Dwight Muhammed Qawi <5ft 4ins = BJW That's not a list of the best p4p fighters under those heights (though Langford arguably is the best sub-5ft 8ins p4p boxer in history), e.g. Henry Armstrong was better p4p than Qawi, but if by - "Not in terms of relative to their division" - you essentially mean in a HW contest/a contest with no upper weight limit, I think the much bigger Qawi would be a more formidible H2H opponent than Armstrong.
1. I understand the OP was asking for the best H2H fighter under the specified height in an uncapped weight limit. I.e. literally who would win out of BJW vs Wolgast with both fighters weighing whatever they want? 2. Brilliant as Wolgast was, 5ft 4ins isn't short for a flyweight. Canto at 5ft even and Perez and 4ft 11ins are better examples of boxers that were short even for flyweights.
Robert Villemain 5'6, maybe 5'7" but often cited at 5'6", an EXCELLENT & Great Fighter, unsung & forgotten. Britain's, Ernie Roderick too.