See also: History of baseball
Baseball evolved from a recreational activity to a professionally organized sport in the mid to late 19th century. Teams were formed and formed the first leagues. These leagues merged until there were over 35 major leagues spread throughout the United States. The first teams began paying their players, ushering in professional baseball.
The most powerful of these leagues was the National League, which had teams in New York City, then the media capital of the US. What caught the attention of New York journalists was widely regarded as the best and biggest in the country. As a result, National League teams received a lot of traffic from the densely populated boroughs of Manhattan or even Brooklyn, which gave them a lot of money and thus a huge advantage over other teams and leagues. They started buying players from other leagues and had them sign contracts that gave the league the right to determine when and where the players would play baseball until the players retired. The players were effectively the property of the league. These contracts soon became known as the Reserve Clause and were one of the most hated aspects of baseball, both by the players and by the other leagues who spent their money to develop talent only to have it snatched away by the National League. Thus, the National League became the first major league.
In the late 1890s, Western League president Ban Johnson decided to challenge the National League. In 1900, he changed the league's name to the American League and promised to sign National League players who were unhappy with their salaries and contract clauses. This resulted in a full-scale war between the two leagues, which came to a head in 1901, worrying Eastern League owner Patrick T. Powers and other independent league owners. They feared that the conflict would spread to their leagues, and so representatives of several independent leagues met at the Leland Hotel in Chicago, Illinois, on September 5, 1901. In response to the war between the two major leagues, the National Association of Professional Baseball Leagues (NABPL or NA for short) was formed - the organization that operates today as the governing body known as Minor League Baseball. Powers became the first president of the NABPL, whose headquarters were established in Auburn, New York. Fourteen leagues (the Eastern League, Western League, New England League, New York State League, Pacific Northwest League, Southern Association, Three-I League, North Carolina League, Connecticut League, Cotton States League, Iowa-South Dakota League, Michigan State League, Missouri Valley League, and the Texas League) signed the agreement and began playing with the new rules in the 1902 season.
The goal of the NA at that time was to ensure the independence of the affiliated leagues. However, many independent leagues preferred not to join the NA and continued to work on their own as they feared the NA would become a new major league and thus jeopardise their independent status. In 1903, the battle between the American and National Leagues ended with an agreement. The NA was involved in the negotiations and negotiated rules that allowed players from NA leagues to be acquired by the major leagues. The NA became involved because players were being outright stolen from clubs in other leagues, for which the club received little, if any, compensation. The 1903 agreement assured these clubs compensation in the future if they sold players they themselves had discovered and promoted to other leagues. No NA team was required to sell players, but many used the money as an important source of revenue.
But the leagues still defended their independence, they still saw themselves as independent sports companies - nothing more, nothing less. Many of the NA stars were as good as many major league stars in the eyes of many journalists. The status of the independent leagues seemed threatened, however, when the U.S. Supreme Court granted baseball organizations special immunity from antitrust laws in 1922, effectively allowing the American and National Leagues to determine the business of the independents. Thus, in 1925, the Major Leagues set a flat rate for NA players of $5,000. This was mainly directed at the Baltimore Orioles, then a Triple-A team whose owner Jack Dunn refused for years to sell outstanding players like Babe Ruth or Lefty Grove to the majors.
The term minor was rarely used, and when it was, it was usually only by major league sportswriters until Branch Rickey developed the first modern farm system in the 1930s. The Commissioner of Baseball at the time, Kenesaw Mountain Landis, didn't like Rickey's idea at all, so he fought it. However, the Great Depression in the U.S. forced Major League teams to set up similar structures to ensure a steady supply of players, as many of the independent and NA teams could not afford to continue operating without help from the Major Leagues, and several leagues ceased play. The NA leagues became subordinate to the majors, becoming the first true minor leagues. With the exception of the Pacific Coast League, which attempted to become a third major league on the West Coast, the leagues kept their names but were completely dependent economically and politically on the National and American Leagues.
During World War II, many professionals were in the U.S. Army, so the number of teams and leagues continued to decline. From 1945 to 1949, the number of leagues in NA briefly increased again from twelve to 59. Since then, the number decreased again and so today there are only 17 minor leagues in the NA, which officially renamed itself Minor League Baseball in 1999. Minor League Baseball still administers the minor league system today, but there are still some leagues that operate independently of the governing body's auspices.
