My theory on the first sries Holsum's (the "H" all the way to the left on back) is that they were the first of all E121 like cards and were issued in late 1920. This is the only set in the E121 family which included the Black Sox players, also it is the only set to use team nicknames on front as opposed to the "American" or Nationals" designation (although most cards in the set are usually found with the later designations, mainly the Chicago players are those with the nicknames). As for dating, Amos Strunk is in the set with Chicago AL and he began the 1920 season with Philadelphia AL and played 58 games with them before going to the Chicago team. Thus, mid-1920 is the earliest the first set could have been produced. I have yet to find a player in the set that began with the team in 1921 and is pictured with that team. So the working timeline is mid-1920. Bob Roth only played with Washington in 1920 with whom he is pictured in the type 1 set, then going to the Yankees for the entire 1921 season (and was produced in E121 Series of 80 for the Yanks)-RhettSome Holsums:Strunk Type 1 (w/ nickname) and Type 2 (w/ Americans)Other Type 1's: