thumb|The [[Commissioner's Trophy (MLB)|Commissioner's Trophy from the Boston Red Sox's 2004 World Series win]]

The World Series has been the annual championship series of the highest level of professional baseball in the United States and Canada since 1903, concluding the postseason of Major League Baseball. Since the Series takes place in October, sportswriters many years ago dubbed the event the Fall Classic; it is also sometimes known as the October Classic or simply The Series. It is played between the League Championship Series winning clubs from MLB's two circuits, the American and National Leagues. The World Series has been played every year since 1903 with the exception of 1904 (boycott) and 1994 (player strike). Though professional baseball has employed various championship formulas since the 1860s, the term "World Series" is usually understood to refer exclusively to the modern World Series.

Although the name "World series" might imply an international competition, no international federation has ever sanctioned the series as a world championship event. Nevertheless, as only a handful of countries have national baseball leagues and, historically, the best baseball players generally play for MLB teams, the winners of the World Series are sometimes informally referred to as "world champions" by fans, players, executives, and the media within the United States and Canada.
The World Series championship is determined through a best-of-seven playoff except for 1903, 1919, 1920 and 1921, when the winner was determined through a best-of-nine playoff. The winning team is awarded the Commissioner's Trophy and the team presents its players and executives individual World Series championship rings. The Series-winning club also receives a larger proportion of the gate receipts from the series.

The New York Yankees of the American League have played in 40 of the 105 World Series and have won 27 World Series championships, most of any Major League franchise. From the National League, the Dodgers have participated the most in the Series with 18 appearances (9 each in Brooklyn and Los Angeles), and have won the Series 6 times (once as Brooklyn, five times as Los Angeles). The St. Louis Cardinals have represented the National League 17 times and have won 10 championships, which is the second most of any Major League Team. Presently, the Chicago Cubs have played the most seasons without winning the World Series, with their last championship coming in 1908. at Baseball Reference

Precursors to the modern World Series (1857–1902)

The original World Series

Until the formation of the American Association in 1882 as a second major league, the National Association of Professional Base Ball Players (1871-75) and then the National League (founded 1876) represented the top level of organized baseball in the United States. All championships went to whoever had the best record at the end of the season, without a postseason series being played. Starting in 1884 and going through 1890, the National League and the American Association faced each other in a series of games at the end of the season to determine an overall champion. These matchups were disorganized in comparison to the modern Series: games played ranged from as few as three in 1884 to a high of 15 in 1887 (Detroit beat St. Louis 10 games to 5), and both the 1885 and 1890 Series ended in ties, each team having won three games with one tie game.

The series were promoted and referred to as the "The Championship of the United States", "World's Championship Series", or "World's Series" for short. As baseball outside of North America was not equal to that of North America at the time, the winners of the championships were by default the best baseball team in the world.

The 19th-century competitions are, however, not officially recognized as part of World Series history by Major League Baseball, as the organization considers 19th-century baseball to be a prologue to the modern baseball era. Until about 1960, some sources treated the 19th-century Series on an equal basis with the post-19th-century series. After about 1930, however, many authorities list the start of the World Series in 1903 and discuss the earlier contests separately.
(For example, the 1929 World Almanac and Book of Facts lists "Baseball's World Championships 1884-1928" in a single table, but the 1943 edition lists "Baseball World Championships–1903-1942".)

According to baseball scholars cited in the Public Broadcasting Service television documentary Baseball: A Film by Ken Burns, players searched worldwide for teams to compete in "World Games" or "World Series" during the late 1800s and early 1900s. Players and promoters such as Albert Spalding would travel the world for teams to play against each other or against American teams. The barn-storming "tours" didn't last long, yet they gave the opportunity to promote sporting goods, as well as to create new leagues and rules. Although the tours did not succeed in spreading baseball to the rest of the world (or in creating foreign teams that would be accepted into the existing annual competition), the title "World Series" has remained.

1892–1900: "The Monopoly Years"

Following the collapse of the American Association after the 1891 season, four of its clubs were admitted to the National League. The league championship was awarded in 1892 by a playoff between half-season champions. This scheme was abandoned after one season. Beginning in 1893 — and continuing until divisional play was introduced in 1969 — the pennant was awarded to the first-place club in the standings at the end of the season. For four seasons, 1894–97, the league champions played the runners-up in the post season championship series called the Temple Cup. A second attempt at this format was the Chronicle-Telegraph Cup series, which was played only once, in 1900.

In 1901, the American League was formed as a second major league. No championship series were played in 1901 or 1902 as the National and American Leagues fought each other for business supremacy.

Modern World Series (1903–present)

Crowd outside Huntington Avenue Grounds before a game during the 1903 World Series

First attempt

After two years of bitter competition and player raiding (in 1902, the AL and NL champions even went so far as to challenge each other to a tournament in football after the end of the baseball season), the National and American Leagues made peace and, as part of the accord, several pairs of teams squared off for interleague exhibition games after the 1903 season. These series were arranged by the participating clubs, as the 1880s World's Series matches had been. One of them matched the two pennant winners, Pittsburgh Pirates of the NL and the Boston Americans (later known as the Red Sox) of the AL; that one is known as the 1903 World Series. It had been arranged well in advance by the two owners, as both teams were league leaders by large margins. Boston upset Pittsburgh by 5 games to 3, winning with pitching depth behind Cy Young and Bill Dinneen and with the support of the band of Royal Rooters. The Series brought much civic pride to Boston and proved the new American League could beat the Nationals.

Boycott of 1904

The 1904 Series, if it had been held, would have been between the AL's Boston Americans (Boston Red Sox) and the NL's New York Giants (now the San Francisco Giants). At that point there was no governing body for the World Series nor any requirement that a Series be played. Thus the Giants' owner, John T. Brush, refused to allow his team to participate in such an event, citing the "inferiority" of the upstart American League. John McGraw, the Giants' manager, even went so far as to say that his Giants were already "world champions" since they were the champions of the "only real major league". At the time of the announcement, their new cross-town rivals, the New York Highlanders (now the NY Yankees), were leading the AL, and the prospect of facing the Highlanders did not please Giants management. Boston won on the last day of the season, and the leagues had previously agreed to hold a World's Championship Series in 1904, but it was not binding, and Brush stuck to his original decision. In addition to political reasons, Brush also factually cited the lack of rules under which money would be split, where games would be played, and how they would be operated and staffed.

During the winter of 1904–05, however, feeling the sting of press criticism, Brush had a change of heart and proposed what came to be known as the "Brush Rules," under which the series were played subsequently. One rule was that player shares would come from a portion of the gate receipts for the first four games only. This was to discourage teams from "fixing" early games in order to prolong the series and make more money. Receipts for later games would be split among the two clubs and the National Commission, the governing body for the sport, which was able to cover much of its annual operating expense from World Series revenue. Most importantly, the now-official and compulsory World's Series matches were operated strictly by the National Commission itself, not by the participating clubs.

With the new rules in place and the National Commission in control, McGraw's Giants decided to show up for the 1905 Series, and beat the Philadelphia A's four games to one. The Series was held in every subsequent season for 89 years.

The list of post-season rules evolved over time. In 1925, Brooklyn owner Charles Ebbets convinced others to adopt as a permanent rule the 2-3-2 pattern used in 1924. Prior to 1924, the pattern had been to alternate by game or to make another arrangement convenient to both clubs.

1919: The fix

Gambling and game-fixing had been a problem in professional baseball from the beginning; star pitcher Jim Devlin was banned for life in 1877, when the National League was just two years old. Baseball's gambling problems came to a head in 1919, when 8 players of the Chicago White Sox conspired to throw the 1919 World Series.

The Sox had won the Series in 1917 and were heavy favorites to beat the Cincinnati Reds in 1919, but first baseman Chick Gandil had other plans. Gandil, in collaboration with gambler Joseph "Sport" Sullivan, approached his teammates and got six of them to agree to throw the Series: starting pitchers Eddie Cicotte and Lefty Williams, shortstop Swede Risberg, left fielder Shoeless Joe Jackson, center fielder Happy Felsch, and utility infielder Fred McMullin. Third baseman Buck Weaver knew of the fix but declined to participate. The Sox, who were promised $100, 000 for cooperating, proceeded to lose the Series in eight games, pitching poorly, hitting poorly and making many errors. Though he took the money, Jackson insisted to his death that he played to the best of his ability in the series (he was the best hitter in the series, but had markedly worse numbers in the games the White Sox lost).

During the Series, writer and humorist Ring Lardner had facetiously called the event the "World's Serious". The Series turned out to indeed have serious consequences for the sport. After rumors circulated for nearly a year, the players were suspended in September 1920.

The "Black Sox" were acquitted in a criminal conspiracy trial. However, baseball in the meantime had established the office of Commissioner in an effort to protect the game's integrity, and the first commissioner, Kenesaw Mountain Landis, banned all of the players involved, including Weaver, for life. The White Sox would not win a World Series again until 2005.

The events of the 1919 Series, seguéing into the "live ball" era, marked a point in time of change of the fortunes of a number of teams. The two most prolific World Series winners to date, the Yankees and the Cardinals, did not win their first championship until the 1920s; and three of the teams that were highly successful prior to 1920 (the Red Sox, White Sox and Cubs) went the rest of the 20th century without another World Series win. The Red Sox and White Sox finally won again in 2004 and 2005, respectively. The Cubs are still waiting for their next trophy.

New York Yankees dynasty (1920–1964)

The New York Yankees signed Babe Ruth from the Boston Red Sox after the 1919 season, appeared in their first World Series two years later in 1921, and became frequent participants thereafter. Over a period of 45 years, 1920 to 1964, the Yankees played in the World Series 29 times. This period reached its apex between 1949 and 1964, when the Yankees reached the World Series 14 times in sixteen years (missing only 1954 and 1959), winning nine. From 1949 to 1953, the Yankees won the World Series five years in a row; no other franchise has won more than three consecutively.

1969: League Championship Series

Prior to 1969, the National League and the American League each crowned its champion (the "pennant winner") based on the best win-loss record at the end of the regular season.

A structured playoff series began in 1969, when both the National and American Leagues were reorganized into two divisions each, East and West. The two division winners within each league played each other in a best-of-five League Championship Series to determine who would advance to the World Series. In 1985, the format changed to best-of-seven.

The National League Championship Series (NLCS) and American League Championship Series (ALCS), since the expansion to best-of-seven, are always played in a 2-3-2 format: Games 1, 2, 6 and 7 are played in the stadium of the team that has home-field advantage, and Games 3, 4 and 5 are played in the stadium of the team that does not.

1971: World Series at night

MLB night games started being held in 1935 by the Cincinnati Reds, but the World Series remained a strictly daytime event for years thereafter. In the final game of the 1949 World Series, a Series game was finished under lights for the first time. The first scheduled night World Series game was Game 4 of the 1971 World Series. Afterwards more and more Series games were scheduled at night, when television audiences were larger. Game 6 of the 1987 World Series was the last World Series game played in the daytime.

1976: The Designated Hitter comes to the World Series

The National and American Leagues operated under essentially identical rules until 1973, when the American League adopted the designated hitter rule, allowing its teams to use another hitter to bat in place of the (usually) weak-hitting pitcher. The National League did not adopt the DH rule. This presented a problem for the World Series, whose two contestants would now be playing their regular-season games under different rules. From 1973 to 1975, the World Series did not include a DH. Starting in 1976, the World Series allowed for the use of a DH in even-numbered years only. Finally, in 1986, baseball adopted the current rule in which the DH is used for World Series games played in the AL champion's park but not the NL champion's. Thus, the DH rule's use or non-use can help the team that has home-field advantage.

1989 earthquake

When the 1989 World Series began, it was notable chiefly for being the first ever World Series matchup between the two San Francisco Bay Area teams, the San Francisco Giants and Oakland Athletics. Oakland won the first two games at home, and the two teams crossed the bridge to San Francisco to play Game 3 on Tuesday, October 17. ABC's broadcast of Game 3 began at 5 p.m. local time, approximately 30 minutes before the first pitch was scheduled. At 5:04, while broadcasters Al Michaels and Tim McCarver were narrating highlights and the teams were warming up, the Loma Prieta earthquake occurred (magnitude 6.9 with an epicenter ten miles (16 km) northeast of Santa Cruz, CA). The earthquake caused substantial property and economic damage in the Bay Area and killed 62 people. Television viewers saw the video signal deteriorate and heard Michaels say "I'll tell you what, we're having an earth--" before the feed from Candlestick Park was lost. Fans filing into the stadium saw Candlestick sway visibly during the quake. Television coverage later resumed, using backup generators, with Michaels becoming a news reporter on the unfolding disaster. Approximately 30 minutes after the earthquake, Commissioner Fay Vincent ordered the game to be postponed. Fans, workers, and the teams evacuated a blacked out (although still sunlit) Candlestick. Game 3 was finally played on October 27, and Oakland won that day and the next to complete a four-game sweep.

1994: League Division Series

In 1994, each league was restructured into three divisions, with the three division winners and the newly introduced wild card winner advancing to a best-of-five playoff round (the "division series"), the National League Division Series (NLDS) and American League Division Series (ALDS). The team with the best league record is matched against the wild card team, unless they are in the same division, in which case, the team with the second-best record plays against the wild card winner. The remaining two division winners are pitted against each other. The winners of the series in the first round advance to the best-of-seven NLCS and ALCS. Due to a players' strike, however, the inaugural NLDS and ALDS were not played until 1995. Home field advantage is given to the team with the better regular season record, with the exception that the Wild Card team cannot get home-field advantage.

1994–95 strike

After the boycott of 1904, the World Series was played every year until 1994 despite World War I, the global influenza pandemic of 1918–19, the Great Depression of the 1930s, America's involvement in World War II, and even an earthquake in the host cities of the 1989 World Series. A breakdown in collective bargaining led to a strike in August 1994 and the eventual cancellation of the rest of the season, including the playoffs.

As the labor talks began, baseball franchise owners demanded a salary cap in order to limit payrolls, the elimination of salary arbitration, and the right to retain free agent players by matching a competitor's best offer. The Major League Baseball Players Association refused to agree to limit payrolls, noting that the responsibility for high payrolls lay with those owners who were voluntarily offering contracts. One difficulty in reaching a settlement was the absence of a commissioner. When Fay Vincent was forced to resign in 1992, owners did not replace him, electing instead to make Milwaukee Brewers owner Bud Selig acting commissioner. Thus the commissioner, responsible for ensuring the integrity and protecting the welfare of the game, was an interested party rather than a neutral arbiter, and baseball headed into the 1994 work stoppage without an independent commissioner for the first time since the office was founded in 1920.

The previous collective bargaining agreement expired on Dec. 31, 1993, and baseball began the 1994 season without a new agreement. Owners and players negotiated as the season progressed, but owners refused to give up the idea of a salary cap and players refused to accept one. On August 12, 1994, the players went on strike. After a month passed with no progress in the labor talks, Selig cancelled the rest of the 1994 season and the postseason on Sept. 14. The World Series was not played for the first time in 90 years. The Montreal Expos were the best team in baseball at the time of the stoppage, with a record of 74-40. (Since their founding in 1969, the Expos, now the Washington Nationals, have never played in a World Series.)

The labor dispute lasted into the spring of 1995, with owners beginning spring training with replacement players. However, the MLBPA returned to work on April 2, 1995 after a federal judge, Sonia Sotomayor, ruled that the owners had engaged in unfair labor practices. The season started on April 25 and the 1995 World Series was played as scheduled, with Atlanta beating Cleveland four games to two.

2003: All-Star Game used to determine home-field advantage

Prior to 2003, home-field advantage in the World Series alternated from year to year between the NL and AL. After the 2002 Major League Baseball All-Star Game ended in a tie, MLB decided to award home-field advantage in the World Series to the winner of the All-Star Game. (It is unclear who would receive home-field advantage if the All-Star Game ends in a tie or if the All-Star Game is rained out.) Originally implemented as a two-year trial from 2003 to 2004, the practice has been extended indefinitely. The American League has won every All-Star Game since this change and thus has enjoyed home-field advantage since 2002, when it also had home-field advantage based on the alternating schedule. The decision has upset some purists (and National League fans). Subsequently, the AL has won the Series four times, and the NL has won three times; no series has gone seven games.

Modern World Series appearances by franchise

World Series record by team or franchise, 1903-2009

==