To try this out, we started a new game in 1932. In real life, the Negro East-West League folded without finishing its season and its players dispersed to other Negro Leagues, but in our alternate reality, the Homestead Grays led the league with a 36-22 record and defeated the Newark Browns in seven games in the championship. The Detroit Wolves finished in third place at 32-26.
As in real life, though, the East-West League vanished after 1933 and the Negro National League reappeared. We simmed forward to see what would happen. (Note that while some Negro Leagues played split seasons, with first half and second half winners, OOTP has them play complete seasons, with a championship series between the top two teams. Given the sometimes messy nature of Negro League schedules, OOTP has to do some simplifying so the game doesn’t break.)
OOTP 18 then continued to march through history. In 1937, the Negro American League opened for business. Meanwhile, Philadelphia clubs dominated the Negro National League between 1933 and 1936: The Stars won three of the four championships and the Bacharach Giants won the other one in 1934, their only year in existence.
We then continued through 1946 – after that season, Negro League players begin signing with MLB clubs. You can break the color barrier any time before 1946, if you want it to fall sooner, but once the 1947 season begins, OOTP 18 allows Negro League players to sign with American and National League teams. After the 1950 season, the Negro Leagues disappear entirely. While a Negro League World Series was held in real life between the Negro American and Negro National Leagues from 1942 to 1948, it doesn’t happen in OOTP 18.