I don't think I've written much, if anything, about Joseph Hollenback. According to E.H. Tobias, Hollenback was the primary force behind the formation of the Empire Club in 1860. Al Spink confirmed that Hollenback was at the first meeting of the club and was elected club secretary. So based just on this information alone, we can say that Hollenback was a reasonably important figure in the history of St. Louis baseball.
However, the problem is that we don't have much more information about Hollenback other than what Tobias and Spink gives us. After researching the subject for several years and chasing several dead ends and false leads, I've gotten to the point where I've organized the information that I have about Hollenback according to what I know to be fact, what I believe to be probable, and what I believe to be possible.
What I know for certain about Hollenback is that he was born around 1836 in New York state. In 1860, he was living in St. Louis at Mrs. Boston's boarding house, was single, and was working as a deputy constable. Hollenback was at the first meeting of the Empire Club on April 16, 1860 and was selected as the club's first secretary.
What is probable about Hollenback is that he was living in St. Louis prior to 1860, that he played baseball in New York prior to moving to St. Louis, and that he played a primary role in the founding of the Empire Club.
What is possible about Hollenback is that he served with Captain Loeblein's Company A, 10th Regiment of the Enrolled Missouri Militia in 1864 and that he died in St. Louis in 1866.
That's really about all I know (or think I know) about Hollenback. I can't even confirm that his last name was spelled "Hollenback."
Tobias writes that Hollenback was a "New Yorker" who "had played with the old Knickerbocker Club" before coming to St. Louis. While I can confirm that Hollenback was born in New York state, I can not confirm that he ever lived in New York City. I also can not confirm that he played with the Knickerbockers and would go so far as to say that it is highly unlikely that he was ever a member of the Knickerbocker Club. I also have not seen any primary source material that confirms Hollenback playing for any club in the New York area. However, Tobias is reasonably reliable source, was a member of the Empire Club, and had access to their records and I believe that he's generally correct in stating that Hollenback lived and played baseball in New York. I just can't prove it. I also believe that Tobias has some reason to write that the "origins of the Empire Club was mainly due to Joseph Hallenbeck" but again I've found nothing that backs Tobias up on this point.
The information about Hollenback's military service and date of death is unconfirmed but simply feels right. If Hollenback joined the army in 1864 and died in 1866, it would explain why there is no mention of him as a member of the Empire Club in the post-war era.
The lack of verifiable information about Joseph Hollenback has been one of the most frustrating things that I've had to deal with while researching the origins of the New York game in St. Louis. However, the research isn't done and I'm certain that more information will, at some point, come to light.