This page presents a chronology of teams and leagues. Events listed include when they were created, moved (between cities or leagues) or disbanded. Also included are some official name changes by Anaheim. However, nickname changes are not discussed here. Some of these franchise connections are not agreed upon by all baseball historians. This list uses the best information available.
| Year | League | Added | Dropped | Moved |
|---|---|---|---|---|
| 1871 | NA | |||
| 1871 | NA | Boston Chicago Cleveland Fort Wayne New York Philadelphia Rockford Troy Washington Olympics | ||
| 1872 | NA | Baltimore Lord Baltimores Brooklyn Atlantics Brooklyn Eckfords Middletown Washington Nationals | Chicago Fort Wayne Rockford Washington Olympics (5/28) Washington Nationals (6/26) Troy (7/23) Middletown (8/9) Cleveland (8/19) | |
| 1873 | NA | Baltimore Marylands Elizabeth Philadelphia White Stockings Washington Nationals | Brooklyn Eckfords Baltimore Marylands (7/11) Elizabeth (8/7) | |
| 1874 | NA | Chicago Hartford | Washington Nationals | |
| 1875 | NA | Keokuk New Haven Philadelphia Centennials St. Louis Red Stockings St. Louis Brown Stockings Washington Olympics | Baltimore Lord Baltimores | |
| 1876 | NA | |||
| 1876 | NA | Brooklyn Keokuk New Haven Philadelphia Centennials Philadelphia White Stockings St. Louis Red Stockings Washington | Boston () Chicago () Hartford () New York () Philadelphia Athletics () St. Louis Brown Stockings () | |
| 1876 | NL | |||
| 1876 | NL | Cincinnati Louisville | Boston Chicago Hartford New York Philadelphia Athletics St. Louis Brown Stockings | |
| 1877 | NL | New York Philadelphia | ||
| 1878 | NL | Indianapolis Milwaukee Providence | Hartford Louisville St. Louis | |
| 1879 | NL | Buffalo Cleveland Syracuse Troy | Indianapolis Milwaukee | |
| 1880 | NL | Worcester | Syracuse | |
| 1881 | NL | Detroit | Cincinnati | |
| 1882 | AA | |||
| 1882 | AA | Baltimore Cincinnati Louisville Philadelphia Pittsburgh St. Louis | ||
| 1883 | NL | Troy (to New York) Worcester to Philadelphia | ||
| 1883 | AA | Columbus New York | ||
| 1884 | AA | Brooklyn Indianapolis Richmond Toledo Washington | ||
| 1884 | UA | |||
| 1884 | UA | Altoona Baltimore Boston Chicago Cincinnati Kansas City Milwaukee Philadelphia Pittsburgh St. Louis St. Paul Washington Wilmington | ||
| 1885 | NL | Cleveland | St. Louis | |
| 1885 | AA | Columbus | ||
| 1885 | UA | |||
| 1885 | UA | Altoona Baltimore Boston Chicago Cincinnati Kansas City Milwaukee Philadelphia Pittsburgh St. Paul Washington Wilmington | St. Louis () | |
| 1886 | NL | Kansas City Washington | Buffalo Providence | |
| 1887 | NL | Indianapolis | Kansas City St. Louis | Pittsburgh |
| 1887 | AA | Cleveland | Pittsburgh () | |
| 1888 | AA | Kansas City | New York | |
| 1889 | NL | Detroit | Cleveland | |
| 1889 | AA | Columbus | Cleveland () | |
| 1890 | NL | Indianapolis Washington | Brooklyn Cincinnati | |
| 1890 | AA | Baltimore Brooklyn Rochester Syracuse Toledo | Baltimore Kansas City | Brooklyn () Cincinnati () |
| 1890 | PL | |||
| 1890 | PL | Boston Brooklyn Buffalo Chicago Cleveland New York Philadelphia Pittsburgh | ||
| 1891 | AA | Cincinnati Washington | Brooklyn Rochester Syracuse Toledo | Cincinnati (to Milwaukee 8/14) Boston |
| 1891 | PL | |||
| 1891 | PL | Brooklyn Buffalo Chicago Cleveland New York Philadelphia Pittsburgh | Boston () | |
| 1892 | NL | Baltimore Louisville St. Louis Washington | ||
| 1892 | AA | |||
| 1892 | AA | Boston Columbus Milwaukee Philadelphia | Baltimore () Louisville () St. Louis () Washington () | |
| 1900 | NL | Baltimore Cleveland Louisville Washington | ||
| 1901 | AL | |||
| 1901 | AL | Baltimore Boston Chicago Cleveland Detroit Milwaukee Philadelphia Washington | ||
| 1902 | AL | Milwaukee (to St. Louis) | ||
| 1903 | AL | Baltimore (to New York) | ||
| 1914 | FL | |||
| 1914 | FL | Baltimore Brooklyn Buffalo Chicago Indianapolis Kansas City Pittsburgh St. Louis | ||
| 1915 | FL | Indianapolis (to Newark) | ||
| 1916 | FL | |||
| 1916 | FL | Baltimore Brooklyn Buffalo Chicago Kansas City Newark Pittsburgh St. Louis | ||
| 1953 | NL | Boston (to Milwaukee) | ||
| 1954 | AL | St. Louis (to Baltimore) | ||
| 1955 | AL | Philadelphia (to Kansas City) | ||
| 1958 | NL | Brooklyn (to Los Angeles) New York (to San Francisco) | ||
| 1961 | AL | Los Angeles Washington | Washington (to Minnesota) | |
| 1962 | NL | Houston New York | ||
| 1965 | AL | Los Angeles ( to California) | ||
| 1966 | NL | Milwaukee (to Atlanta) | ||
| 1966 | AL | California (to Anaheim) | ||
| 1968 | AL | Kansas City (to Oakland) | ||
| 1969 | NL | Montreal San Diego | ||
| 1969 | AL | Kansas City Seattle | ||
| 1970 | AL | Seattle (to Milwaukee) | ||
| 1972 | AL | Washington (to Texas) | ||
| 1977 | AL | Seattle Toronto | ||
| 1993 | NL | Colorado Florida | ||
| 1997 | AL | California ( to Anaheim) | ||
| 1998 | NL | Arizona | Milwaukee | |
| 1998 | AL | Tampa Bay | Milwaukee () | |
| 2005 | NL | Montreal (to Washington) | ||
| Year | League | Added | Dropped | Moved |