Brock was best known for breaking Ty Cobb's all-time major league stolen base record in 1977. He was an All-Star for six seasons and a National League (NL) stolen base leader for eight seasons. He led the NL in doubles and triples in 1968. He also led the NL in singles in 1972, and was the runner-up for the NL Most Valuable Player Award in 1974.
Brock was born in El Dorado, Arkansas, to a family of sharecroppers. His family moved to Collinston, Louisiana, when he was two years old. While his family didn't have much money, he said that he never felt poor because, "If you don't have something, you don't miss it." Brock grew up as a fan of the Brooklyn Dodgers, the team that included Jackie Robinson, Don Newcombe and Roy Campanella. Although he didn't play in organized baseball until he reached the 11th grade, he learned much about the sport from listening to Cardinals radio broadcaster Harry Caray describe the way major league hitters stood at the plate. After attending high school in Mer Rouge, Louisiana, he received academic assistance to attend Southern University in Baton Rouge, but when a low grade in his first semester meant the possibility of losing his scholarship, he decided to try out for the school's baseball team in order to secure an athletic scholarship.
Brock hit for a .189 batting average in his first year of college baseball, but improved the following year to hit for a .500 average. Southern University won the NAIA baseball championship during his junior year, and Brock was selected for the United States baseball team in the 1959 Pan American Games. When Brock decided to try for a professional baseball career, he traveled to St. Louis to try out for the Cardinals, but the scout who had recommended him was in Seattle to sign Ray Washburn. He then decided to try out for the Chicago Cubs, who signed him as an amateur free agent in 1960. Assigned to play for the St. Cloud Rox, Brock won the 1961 Northern League batting championship with a .361 batting average. It would be his only season in minor league baseball as the Cubs decided to promote him to the major leagues.
Brock made his major league debut with the Cubs on September 10, 1961, at the age of 22. In his rookie season of 1962, Brock became one of four players to hit a home run into the center-field bleachers at the old Polo Grounds in New York since its 1923 reconstruction. His blast came against Al Jackson in the first game of a June 17 doubleheader against the New York Mets and was one of two that would clear the wall in consecutive days, with Hank Aaron's coming the very next day. Joe Adcock was the first to hit a ball over that wall, in 1953. Babe Ruth reached the old bleachers (a comparable distance) before the reconstruction. Brock was not known as a power hitter, but he did display significant power from time to time.
Brock had great speed and baserunning instincts, but the young right fielder failed to impress the Cubs management, hitting for only a combined .260 average over his first two seasons. In 1964 after losing patience with his development, the Cubs gave up on Brock and made him part of a trade with the St. Louis Cardinals. The June 15 deadline deal for pitcher Ernie Broglio saw Brock, Jack Spring, and Paul Toth head to St. Louis for Broglio, Bobby Shantz, and Doug Clemens. Cardinals general manager Bing Devine specifically sought Brock at the insistence of Cardinals' manager Johnny Keane to increase team speed and solidify the Cardinals' lineup, which was struggling after the retirement of left fielder Stan Musial in 1963. At the time, many thought the deal was a heist for the Cubs. Broglio had led the National League in wins four years earlier, and had won 18 games the season before the trade.
After Brock was traded to the Cardinals, his career turned around significantly. He moved to left field and batted .348 and stole 38 bases for the remainder of the 1964 season. At the time of the trade, the Cardinals were 28–31, in eighth place in the National League, trailing even the Cubs, who were 27–27 and in sixth place. Brock helped the Cardinals storm from behind to capture the National League pennant on the last day of the season. Four months to the day after Brock's trade, the Cardinals would win the 1964 World Series in seven games over the favored New York Yankees, who were appearing in their fourteenth World Series in sixteen years (and their last until a dozen years later). Brock's contributions to the Cardinals' championship season were recognized when he finished in tenth place in voting for the 1964 National League Most Valuable Player Award. Meanwhile, Broglio won only seven games for the Chicago Cubs before retiring from baseball after the 1966 season. To this day, the trade of Brock for Broglio is considered one of the most lopsided deals in baseball history.
In 1966, Brock ended Maury Wills' six-year reign as the National League's stolen base champion with 74 steals. In David Halberstam's book, October 1964, the author states that manager Johnny Keane asked Brock to forgo hitting home runs in favor of the stealing bases. Brock went on to lead the National League in stolen bases eight times within a nine-year span between 1966 and 1974 (former teammate Bobby Tolan led the league in steals in 1970). Brock began the 1967 season by hitting 5 home runs in the first four games of the season, becoming the first player to do so (Barry Bonds would tie this record in 2002). He was hitting for a .328 average by mid-June to earn the role as the starting left fielder for the National League in the 1967 All-Star Game. After suffering through a mid-season slump, he recovered to finish the season with a career-high 206 hits and a .299 batting average while leading the league in stolen bases and runs scored as the Cardinals won the National League pennant by ten and a half games. Brock became the first player to steal 50 bases and hit 20 home runs in the same season. In the 1967 World Series, Brock hit for a .414 average, scored 8 runs and set a World Series record with seven stolen bases as the Cardinals defeated the Boston Red Sox in seven games.
The Cardinals won the National League pennant for a second consecutive year in 1968 as Brock once again led the league in stolen bases as well as in doubles and triples. In the 1968 World Series against the Detroit Tigers, Brock had three stolen bases in Game 3 and contributed a double, triple, home run and four runs batted in during Game 4 to help the Cardinals build a three-game to one advantage over the Tigers. The Cardinals appeared to be on the verge of winning a second consecutive World Series, going into the fifth inning of Game 5 with a 3–2 lead. Although Brock's base running abilities had proven to be a factor in the previous four games, his carelessness may have cost the Cardinals a run. After Brock had hit a double, he tried to score standing up on Julián Javier's single to left, but Willie Horton threw him out with a strong throw to home plate. Detroit rallied for three runs in the seventh inning as Mickey Lolich shut out the Cardinals for the final eight innings to win the game for the Tigers. In Game 7, Brock had another crucial miscue when he was picked off base by Lolich, extinguishing a possible Cardinals rally. The Tigers rallied from being down three games to one behind the excellent pitching of Mickey Lolich to win the series. Brock once again stole seven bases and was the leading hitter in the series, posting a .464 batting average with 6 runs and 5 runs batted in.
At the end of the 1960s, Brock's career was entering its prime. Beginning in 1969, he produced six consecutive seasons with 190 hits or better. He was named NL Player of the Month for the first of three times in his career in May 1971 with a .405 batting average and 8 stolen bases. In August 1973, he broke a record set by Ty Cobb when he stole his 50th base of the season, marking the ninth time he had stolen 50 or more bases in a season. Brock won his second NL Player of the Month Award in August 1974, with 29 stolen bases in 30 games, despite batting only .326; also, he was the first batter to be named Player of the Month without hitting a home run in the month of his award.
On September 10, 1974, Brock stole two bases, tying Maury Wills' mark of 104 with a first inning steal of second base and then capturing sole possession of the single season record with another swipe of second in the seventh inning. He ended the season with a new major league single-season record of 118 stolen bases. Brock finished second to Steve Garvey in the balloting for the 1974 National League Most Valuable Player Award.
In a game against the San Diego Padres on August 29, 1977 at Jack Murphy Stadium in San Diego, Brock became the all-time major league stolen base leader when he broke Ty Cobb's career record of 892 stolen bases. The record had been one of the most durable in baseball history and like Babe Ruth's record of 714 career home runs, had been considered unbreakable by some observers.
Brock remained best known for base-stealing and starting Cardinals rallies. He was said to have disdained Maury Wills' method of base-stealing, instead shortening his leads and going hard. He was also an early student of game films. He used an 8 mm movie camera from the dugout to film opposing pitchers and study their windups and pickoff moves to detect weaknesses he could exploit.
Brock fell into a hitting slump early in the 1978 season and lost the left fielder's job. However, he fought back during spring training in 1979 with a .345 batting average to regain his starting job. Brock was named Player of the Month for the month of May 1979, during which he produced a .433 batting average.
On August 13, 1979, Brock became the fourteenth player in Major League Baseball history to reach the 3,000 hits plateau against the team that traded him, the Chicago Cubs. Approximately one month later, Carl Yastrzemski reached the same plateau and was promptly invited to the White House by Massachusetts Congressman Tip O'Neill. Brock was reported to have felt slighted that he hadn't received a similar invitation. Brock originally stated that he wouldn't go to the White House even if he was invited. However, after consideration he decided that forgiveness was the best course and accepted a belated invitation to meet with the President. Brock retired at the end of the season, having posted a .304 batting average in his last season at the age of 40. At the end of the season, he was named the National League Comeback Player of the Year—the first player to be so named in his final Major League season.
In a nineteen-year major league career, Brock played in 2,616 games, accumulating 3,023 hits in 10,332 at bats for a .293 career batting average along with 149 home runs, 900 runs batted in, 1,610 runs scored, and a .343 on-base percentage. A six-time All-Star, Brock hit over .300 eight times during his career. He ended his career with a .959 career fielding percentage.
Brock held the single-season stolen base record with 118 until it was broken by Rickey Henderson in 1982. He also held the major league record for career stolen bases with 938 until it was also broken by Henderson in 1991. He led the National League in stolen bases for a record eight times and also had a record twelve consecutive seasons with 50 or more stolen bases. Brock is still the National League's leader in career stolen bases.
Brock's .391 World Series batting average is the highest for anyone who played over 20 series games. His 14 stolen bases in World Series play are also a series record. Brock's 13 hits in the 1968 World Series tied a single-series record previously made by Bobby Richardson in 1964 against his Cardinals' team, and later tied in 1986 by Marty Barrett.
In a unique (if incidental) accomplishment, Brock was the first player ever to bat in a major league regular season game in Canada. Leading off against Montreal Expo pitcher Larry Jaster (a Cardinal teammate of Brock's just the year before, who had been acquired by the Expos in that offseason's expansion draft) in the Cardinals' April 14, 1969 game at Jarry Park, he lined out to second baseman Gary Sutherland.
Brock received numerous awards during his playing career. In January 1968 he was named the recipient of the Babe Ruth Award as the outstanding player in the 1967 World Series. Brock was honored with The Sporting News Player of the Year Award in 1974. In the wake of his record setting 118 stolen bases during the 1974 season, Brock was named the winner of the Roberto Clemente Award in March 1975, for best exemplifying the game of baseball both on and off the field. In 1977 he was awarded the Lou Gehrig Memorial Award as the player who best exemplified Lou Gehrig's ability and character. In 1978, the National League announced that its annual stolen base leader would receive the Lou Brock Award, making Brock the first active player to have an award named after him.
In October 1979, Brock was named the National League's Comeback Player of the Year. In December 1979, he was named as the recipient of the Hutch Award, given to the player who best exemplifies the fighting spirit and competitive desire of Fred Hutchinson. Also in 1979, the St. Louis Cardinals retired Brock's jersey number 20, an honor that had previously been bestowed upon only three other Cardinals players; Stan Musial, Dizzy Dean and Bob Gibson. In 1983 he was inducted into the Louisiana Sports Hall of Fame. In 2014, the Cardinals announced Brock among 22 former players and personnel to be inducted into the St. Louis Cardinals Hall of Fame Museum for the inaugural class of 2014.
Brock was inducted into the Baseball Hall of Fame in 1985, his first year of eligibility. He was inducted into the Missouri Sports Hall of Fame in 1992. Brock was inducted into the St. Louis Walk of Fame in May 1994 and, in 1995 he was inducted into the Arkansas Sports Hall of Fame. In 1999, he was ranked Number 58 on The Sporting News' list of the 100 Greatest Baseball Players, and was nominated as a finalist for the Major League Baseball All-Century Team.
After retiring from baseball, Brock prospered as a businessman, especially as a florist in the St. Louis, Missouri area. He briefly worked as a color analyst for Monday Night Baseball on ABC in 1980, and for Chicago White Sox telecasts the following year. Brock still regularly appears at Cardinals games. When he steps onto the field he is always greeted by a loud, low-pitched cheer of "Loooouuuuuuuuuuuu". He also lent his name to a unique rainhat, shaped like a miniature umbrella and to be worn at games during showers in lieu of retreating to the concourse. The product was called the "Brockabrella."
Brock and his wife are both ordained ministers serving at Abundant Life Fellowship Church in St. Louis, and he is a director on the board of YTB International. Brock's speed was referenced in the song Check the Rhime by the pioneering "jazz rap" hip-hop ensemble A Tribe Called Quest. On December 5, 2006 he was recognized for his accomplishments on and off of the field when he received the Bobby Bragan Youth Foundation Lifetime Achievement Award. Brock is the father of former University of Southern California Trojan and National Football League player Lou Brock Jr.
Brock's left leg was amputated below the knee in October 2015 because of an infection related to a diabetic condition.
He announced on April 13, 2017, that was diagnosed with multiple myeloma, a blood cancer that starts in the bone marrow's plasma cells.
On July 28, 2017, Brock and his wife, Jackie, said they had received word from Mercy Hospitals doctors that, according to their blood tests, the cancerous cells were gone. "Brock said the cancer had been declining for some time. “We got reports that it was 25 percent gone, then 50 percent, then 75 percent gone,” he said. “The doctors were absolute. (The cancer) is not there.”