On December 10, 1924, the American League and National League agreed to a rotation system for the World Series. According to the agreement, Games 1 and 2 would take place at one league’s park, the next three at the other team’s home field, with the final two games (if needed) back at the first venue. The NL was granted the inaugural advantage in following season’s Fall Classic.
1925 World Series booklet (milehighcardco.com)