Schmeling for sure. He was either heavyweight champion or a leading contender for 80% of the decade. He also was the only man to beat Louis during the 1930’s.
Another contender who should be considered for this title is Tommy Loughran. He is the best HW from this era Louis did not fight. He lost to Farr but beat Braddock and Max Baer went 1-1-1 with Godoy and has a very stellar record against large opponents. If Loughran had won the title he might be the consensus answer to this question.
Schmeling's record in the 30's was 10-4-1. He has that win over Louis, but I'm not sure he has the 2nd best HW record solely in the 30's. I do think Schmeling at his best was the 2nd best HW who competed during the 30's, though.
Schmeling was 10-4-1 during the 30s. Only 10 wins, but excellent wins over Louis (1-1), Sharkey DQ (1-1) though his loss was debatable, Uzcudun, Hamas (1-1), Stribling, Walker and Neusel. His other loss was to Baer. Baer went 45-11, beating Schmeling, Carnera, Farr (1-1), Schaaf (1-1), Heeney, Levinsky x 2 and Wright. He also lost to Loughran, Risko, Uzcudun, Braddock and Louis around his prime. Nova went 22-2-4. He beat Baer, Farr, Simon, Barlund and Ramage (1-0-1). He drew with Pastor. He lost to Rosenbloom and Galento. Carnera went 64-12, though was 61-6 before badly fading away past prime. He beat Sharkey (1-1), Loughran, Uzcudun x 2, Schaaf, Levinsky x 2 and Neusel. He also lost to Louis, Poreda, Gains and Baer around his prime years. Unless I've missed anyone obvious, these are the clear contenders. In retrospect, having done this analysis, I retract my earlier statement, I am certain Schmeling has the 2nd best HW record during the decade. Even without Louis you could argue he has the highest quality win resume. With Louis, there is no argument, he clearly does. For comparison, whilst he finished with a nice little run, Braddock went 15-18-1 at HW during the 30s, which is why that run earned him the nickname Cinderella Man. He'd been that poor before it.
You can make strong cases for Schmeling Sharkey and Baer. Outside of that trio, everybody is fighting for fourth place.
Strictly factoring in contests in the 30s alone I don't see an argument for Sharkey being above Carnera, Nova or Loughran, amongst others. Sharkey went 5-6-1 in the 30s, which would have been 4-7-1 had the official Schmeling 2 decision gone the way most felt it should have. Jack's only other notable win was over Carnera and was avenged by Primo.
If you set aside your rule that you can only factor in fights that happened in teh 30s, then I could make a strong case for Sharkey. If you stand on your rule, then I have no choice but to agree with you.
Joe was so far ahead of the rest,was n't he? I would say Schmelling on the strength of his win in his first fight with Louis.
Agreed, based on their entire careers Sharkey is probably 4th, behind Louis, Schmeling and Baer. Based on the conditions laid out in the OP, I.e. 2nd best record in the 30s only, Sharkey is nowhere.
So after reading everyone's interesting takes I decided to see what Ring Magazine had to say. I took their champion and top ten contenders for each year of the decade and assigned point values. I gave 15 points to the belt holder followed by ten points for the #1 ranked guy, 9 points for the second ranked fighter and so on down to one point for the man in the 10th spot. Below are the top 20 guys ranked in order of points. The second number is how many years they were the champ or in the top ten. I think it is clear they would say Schmeling is the number two man for the decade. As a side note, the only two years Braddock was in the top ten were the two years he was champion. He truly was a Cinderella Man. Schmeling-89-9 Louis-66-6 Baer-45-6 Carnera-43-5 Sharkey-35-3 Braddock-30-2 Levinsky-25-4 Galento-23-4 Nova-22-3 Pastor-21-4 Schaaf-19-3 Farr-17-3 Loughran-14-3 Stribling-13-2 Rosenbloom-12-2 Hamas-12-2 Poreda-11-2 Barland-11-2 Criffiths-10-2 Perroni-10-2