Baseball is long thought to have started in the middle of the year 1845. The game that was seen back in 1845 consisted essentially just of the fundamentals of baseball today and none of the extra stuff. Nine players on each team, defense has ball, offense has bat, and the pitcher wants to get the batter out so that they can go on offense. This early version of baseball was often called yard ball, and also grew in popularity especially during the Civil War in the 1860's.
In 1903, the MLB was officially formed after the merging of two national baseball leagues, the National League, and the American League. In addition to this merging, the World Series was created, in which the then Boston Americans won against the Pittsburgh Pirates 5-3. the next year, however, the World Series was not held anywhere because the New York Giants absolutely refused to play the Boston Americans because the Giants' commisioner thought they were "inferior". There was also no World Series in 1994 because the players went on strike.
The 1920's are often referred to as the golden age for sports in America. The 1920's introduced the famous outfielder, Babe Ruth. Babe Ruth went away with the "infield game" era where bunts and sacrifices were often and brought explosion to home plate when batting. Free swinging to the ball brought home runs and a guaranteed win for your team, which was Ruth's ideal vision of the game of baseball.
From 1942 to the end of World War II, many people were wondering if the play of the official Major League Baseball teams in a season should be suspended until the end of the war. President Roosevelt, a baseball fan himself, felt that baseball was valuable and vital to the nation and the nation's morale in a letter he wrote on January 15, 1942. from this moment on, American baseball threw itself behind the war effort, often being called "the national nerve tonic" for workers and soldiers in and out of the country.