The current Orioles didn't get their start in St. Louis, though. Their first home was Milwaukee, where they finished in the AL cellar in 1901. When they moved to St. Louis the next year, they lured several valuable players from the city's NL Cardinals—including 1901 batting champ Jesse Burkett, star shortstop Bobby Wallace, and the Cards' three best pitchers. They also took on the Cardinals' discarded nickname, becoming the new St. Louis Browns.

The Browns finished a strong second to the Philadelphia Athletics in their first St. Louis season, but fell to sixth the next year and, except for a fourth-place finish in 1908 (thanks to the pitching of newly acquired veteran Rube Waddell), remained mired in the second division until 1920. Late in the 1913 season a young Branch Rickey was hired to manage the Browns. In his two full seasons he was unable to lift the club out of the second division, but he did sign college star George Sisler (whom he had coached at the University of Michigan), who became, as the Browns' first baseman, one of the game's all-time greats.

In 1916, his first full season, Sisler led the Browns in hitting as they caught fire in August to record their first winning season in eight years. Pitcher Urban Shocker was obtained from the Yankees two years later and by 1920 had developed into a 20-game winner. Also in 1920, Sisler batted .407 and connected for 257 hits, still a major league record, to help move the Browns up to fourth, their highest finish since 1908 (though their won-lost record of 76-77 remained on the losing side). The next year Shocker's 27 victories brought them a winning season and third place. And in 1922 the team recorded its finest record ever in St. Louis: 93 wins and a .604 winning percentage.

The 1922 Browns, led by Sisler's sizzling .420 batting average, hit .313 as a team to lead the league. Left fielder Ken Williams ran away with the RBI title and beat out Babe Ruth and Tilly Walker for the home run crown (although Ruth did miss nearly a third of the season that year). Sisler and Williams even finished one-two in AL stolen bases. And though Shocker slipped a bit to 24 wins, he led a pitching staff that recorded the league's lowest ERA. The team led the league in the standings throughout July and into August before the Yankees nudged ahead of them. The Browns hung close but didn't regain the lead, remaining second, a heartbreaking single game back, at season's end.

Falling back to fifth the next year, as Sisler missed the whole season with a sinus infection, the Browns remained out of contention for the next 21 years, dropping to their lowest point in 1939, 64½ games out of first, with 111 losses. They recovered for three winning seasons in the war years 1942–45, finishing a distant third in 1942, and capturing their only St. Louis pennant in 1944, edging the Detroit Tigers on the final day after trailing them through most of September. The World Series—an all-St. Louis affair—proved anticlimactic for the Browns as they lost to the Cardinals in six games.

The Browns finished third in 1945 before sinking back into the second division. Even the club's purchase by the dynamic Bill Veeck in July 1951 couldn't rouse them out of the depths. (A month after buying the Browns, Veeck made his best-remembered move: bringing in Eddie Gaedel, a midget, for one plate appearance. Gaedel walked.)

Unable to earn either victories or money in St. Louis, Veeck in September 1953 sold the club to a Baltimore group, who moved the Browns and renamed them the Orioles. The new owners hired the brilliant Paul Richards to rebuild the team. As manager, both in the front office and on the field, Richards (and Lee MacPhail, who became general manager and president in 1958) took several years to move the Orioles above .500. In 1960, with young third baseman Brooks Robinson and rookie Jim Gentile, the team made its first run for the pennant since 1944. In first place in early September, they finished second when the Yanks won 15 straight to pass them by.

The next year the Orioles did even better, winning six more games than they had in 1960 as Gentile hit 46 home runs and drove in 141. But it was an even better year for New York and Detroit, and Baltimore finished a distant third.

When Hank Bauer was brought in to manage the Orioles in 1964, the team entered its golden decades—20 years that saw them win seven division titles, six pennants, and three world championships, with only two finishes below third. With Robinson driving in runs and left fielder Boog Powell slugging at a league-leading pace, the O's finished 1964 with wins in seven of their final eight games. But the White Sox won their last nine and the Yankees put together an 11-game streak near the end to take the flag and leave Baltimore in third, two games back.

After another third-place finish in 1965, the Orioles acquired slugger Frank Robinson from Cincinnati and moved second-year pitcher Jim Palmer into the starting rotation. Palmer won 15 to lead a balanced staff, and Frank Robinson captured the Triple Crown. With both Robinsons and Powell driving in 100 runs or more, the O's romped to their first Baltimore pennant. They continued the romp in the World Series, holding Los Angeles to a total of just two runs as they swept to their first world title.

A drop in offensive production and the loss of Palmer to injuries for most of the season plunged Baltimore into a tie for sixth in 1967. Palmer was out the next year, too, but pitchers Dave McNally and Jim Hardin burst to the forefront with fine seasons to lift the club back to second.

Baltimore Coach Earl Weaver, a pennant-winning manager in the O's farm system, replaced Hank Bauer at the Orioles' helm in mid-1968 to begin what became one of the longest and most successful managerial tenures of recent times. In 14 full seasons Weaver led his club to six Eastern Division titles and six second-place finishes, with one season each in third and fourth. His teams featured fine hitters and fielders, but the pitching performances stand out above the rest. In 7 of the 14 years the Oriole staff compiled the league's lowest ERA, including five consecutive seasons (1969–73). Oriole pitchers put together in those 14 years 21 seasons of 20 wins or more (8 of them by Jim Palmer), and garnered six Cy Young Awards.

In the first three years of division play (1969–71), Baltimore ran away with the East championship and swept to the pennant each time in the League Championship Series. The 1969 team (despite an embarrassing loss to the New York Mets in the World Series) is often ranked among the greatest of all time. With overwhelming pitching and fielding, the Orioles took the division crown by 19 games, winning a club-record 109. In fielding, seven percentage points separated the AL's second-best team from the worst; the Orioles fielded three points better than the second-best team. And Oriole pitchers gave up nearly a run less per game than the league average. Baltimore's performance in 1970 was nearly as impressive. Mike Cuellar and Dave McNally won 24 games each, and Jim Palmer contributed 20 more wins to the O's total of 108. They won the World Series as well as the pennant, rolling over Cincinnati in five games.

In the 1971 World Series, though, Pittsburgh came back from losses in the first two games to defeat the Orioles by a run in Game 7. The O's captured division titles in 1973 and 1974, but it was 1979 before they again triumphed in the ALCS. Once again, however, they faced the Pirates in the World Series, and once again they took the Series lead, only to fall in the seventh game.

The 1979 pennant was Weaver's last, as late-season Oriole surges in 1980 and 1982 fell just short. But in 1983 the O's—paced by the pitching of veteran Scott McGregor and rookie Mike Boddicker, and the hitting and fielding of Cal Ripken Jr. at short and Eddie Murray at first—made new Manager Joe Altobelli look good. After a comfortable division win, they trounced Chicago's White Sox in the LCS and the Philadelphia Phillies in the World Series.

Declining after 1983 despite the return of Earl Weaver in 1985–86, the Orioles finished last in the East in 1986. Though they rose to sixth in 1987, their .414 winning percentage was their lowest in 32 years. Then in 1988 they hit rock bottom, not only finishing last but also beginning the season with an AL record-setting 21 consecutive defeats.

Baltimore's rebound was even more startling than its plummet. Under Manager Frank Robinson (who had been handed the hapless O's early in the 1988 season), the 1989 Orioles took over first place in late April, held the lead through August, and stayed within reach of the division title until Toronto defeated them in the season's penultimate game to clinch the crown. The newly potent bat of catcher Mickey Tettleton and splendid relief from rookie Gregg Olson highlighted the Baltimore resurgence. Olson remained effective in 1990, but the offense faltered, and an August-September slide dropped the Orioles out of the race.

The O's began slowly in 1991, and Manager Robinson was replaced by Coach Johnny Oates in May, with the club in last place. But although Cal Ripken put together an MVP season, the O's never caught fire and finished sixth, 24 games out. In 1992, though, playing in the festive new Oriole Park at Camden Yards, Baltimore snapped back to challenge Toronto through much of the season before slipping to third, seven games out.

At a bankruptcy auction in August 1993, a group led by Peter Angelos agreed to purchase the club for a record $173 million. On the field, 1993 was much like 1992 had been. Only half a game out of first as late as September 9, the Orioles finished 10 games back, tied for third with Detroit.

They challenged again in 1994, however, they slipped from just half a game behind the division-leading Yankees at midseason to 6½ games out by the time the players' strike brought the season to a close in August. The second-place finish was not good enough to save manager Oates' job.

Nineteen ninety-five was the year of Cal Ripken, Jr. as he finally broke Lou Gehrig's consecutive game playing streak. But otherwise it was a disappointing season as Baltimore loaded up on such high-priced talent as Bobby Bonilla and Rafael Palmeiro but still finished only 71-73.

After managing for 10 years in the National League, Davey Johnson brought power baseball to Baltimore. His job was made easy by a team that belted a Major League-record 257 home runs (led by Brady Anderson's 50 long balls) and qualified for postseason play as a wildcard. Despite controversy surrounding Roberto Alomar and Cal Ripken, the team managed to win 88 games while losing 74. The Orioles, with new acquisitions Mike Bordick, Eric Davis and Jimmy Key are expected to be a powerhouse contender, capable of going deep into the post season.

Information taken from Total Baseball IV: The Official Encyclopedia of Major League Baseball and the 1997 Official Major League Baseball Fact Book, published by the Sporting News.