There is an entry for the club over at Protoball that was added by Bruce Allardice:
The Freeport Journal, June 6, 1866, has a lengthy and interesting article titled "Empire Base Ball Club...History of the Club." The detailed article says the club was formally organized May 26, 1862, but couldn't find a team to play against until they played the Garden City of Chicago in a home and home tournament June 10, July 4, 1863. The Empire won the latter game and, according to the newspaper, "was pronounced the Champion club of the State." They played the Empire of St. Louis July 4, 1865, losing 27 to 20. On Sept. 29, 1865 they beat the Julian of Dubuque, at Dubuque, 27 to 26. The article gives the names of the organizers of the team and the current players.
The Freeport Weekly Journal, April 12, 1865: "the Empire Base Ball Club have again reorganized" with "John Neff, president" and "A. Brewster, capt. on field."
Same, Aug. 2, 1865, reports that "Monday" the Empires visited the Forest City of Rockford, beating them 55-21.
The Freeport Journal April 3, 1867, under the headline "Base Ball Club" reports on the "reorganization" of the "Empire Base Ball Club of this city". W. B. Thomas was elected president and captain. An initiation fee of $1.00 was set.
Same June 7, 1867 has the Empire defeating the Stars 10-9.
There are two things that I think are significant in the information that Bruce gives us. First, Freeport was a club that was founded during the Civil War. I'm of the opinion that clubs that competed during the war years had an advantage in the immediate post-war period. They had more experience than those clubs that started up right after the war. And there weren't a lot of these clubs. I don't have all the data but there weren't many clubs that existed during the war and continued to compete in the post-war baseball fever era. So I think that an experienced club with good players had an advantage over the new post-war clubs. Freeport was one of those experienced clubs with good players who had been together for a few years and knew how to play the game. The Empires were another a club like that.
And, real quick, lets settle the name thing right now. We have two clubs, both named Empire - the Empire Club of Freeport and the Empire Club of St. Louis. I will, throughout this series refer to the Empire Club of Freeport simply as Freeport. I will refer to the Empire Club of St. Louis as the Empire Club or the Empires. Okay?
The second really interesting piece of information that Bruce gives us is that Freeport were the champions of Illinois in 1863. They had victories over clubs from Chicago, Dubuque, and Rockford. There is no doubt that they were a very good club.
That's an important piece of information and one that's new to me. I didn't know if Freeport was any good or not but now I can say that we know for a fact that they were a good baseball club. That's significant because the basis for the Empire Club's claim to the Championship of the West is based largely on their victory over Freeport (and I'm really sorry if I just gave away the ending). In the past, I always thought that was a rather weak claim. You beat Freeport twice and a club from Dubuque and all the sudden you proclaim yourself to be champions? That seemed a bit sketchy to me. But now I think we can say that in the Freeport club, the Empires had found a worthy foe and that it's very likely that the game on July 4, 1865, matched the best club in Illinois against the best club in Missouri.