What would later be called the First World War had, by the spring of 1918, been in full throat for nearly four years in Europe. The United States, which had entered the war in April of 1917, was finally mobilized and had recently sent the American Expeditionary Force under General John Pershing, to France. In other words, the U.S. was now fully invested in the war, which had not been the case during the previous baseball season. While the impact in terms of player talent was still minimal in 1918 as most players stayed in their regular (baseball) uniform, the FABL Commission decided to shorten the season and the Fed & Continental league campaigns would end a month earlier than usual.
The Chicago Chiefs were the original professional baseball club, created in 1876 alongside seven other clubs; only they and the Philadelphia Keystones (who were then called the Centennials) remained. And while the Chiefs had often been good, they had not won a pennant since 1881. In the span of the 35 seasons that followed, the Chiefs finished second nine times and third seven more. Sure, there were some very lean years in there too, but in general, the Chiefs were a decent club that just couldn't get over the final hurdle and capture the pennant. In 1917, that finally changed.