This iconic Jackie Robinson moment, when he stole home under the tag of Yogi Berra during the World Series, took place in 1955. If not for the bigotry of the 1880s and 1890s, Robinson would not have had such a barrier to break through. (John Rooney/Associated Press)

His plaque in Cooperstown, N.Y., was in need of amendment, or editing, the moment it was unveiled at the National Baseball Hall of Fame in 1939. To be sure, of the achievements it cited of Adrian Constantine Anson, better known as Cap — “GREATEST HITTER AND GREATEST NATIONAL LEAGUE PLAYER-MANAGER OF 19TH CENTURY . . . .300 CLASS HITTER 20 YEARS . . . ” — it omitted his most remarkable.

Cap Anson erected the color barrier in baseball.

His effort to make baseball all white — which, disturbingly, didn’t deter us from fondly calling it America’s pastime — became the game’s hallmark for more than half a century: 60 years. But there is no acknowledgement in Anson’s Hall of Fame display of his role in spearheading racial segregation in baseball, which as this country’s bellwether professional sport led our other professional team sports, including the NFL and NBA, as well as popular individual sports, most notably heavyweight boxing and golf, to shun athletes of color as well.

Princeton University last month was forced to confront its historically sterilized celebration of one of its icons — alumnus, former university president and 28th U.S. President Woodrow Wilson. It hadn’t adequately acknowledged his past as a maker of racist public policy that had a deleterious impact on countless black citizens.

Well, Cap Anson is baseball’s Woodrow Wilson problem. And the game ought to take a lead from Princeton on how to correct it.

Cap Anson poses for a formal portrait. Anson played in Chicago for the White Stockings from 1876-1889 and the Colts from 1890-1897. He also refused to take the field against black players. (National Baseball Hall of Fame/MLB Photos via Getty Images)

Princeton agreed late last month to examine what to do about the standing on its campus of Wilson, after a group of students staged a sit-in to protest actions Wilson took as a policymaker that thwarted equal opportunity for progeny of enslaved Africans. As a New York Times editorial titled “The Case Against Woodrow Wilson at Princeton” reminded last week: “[Wilson] was an unapologetic racist whose administration rolled back the gains that African-Americans achieved just after the Civil War, purged black workers from influential jobs and transformed the government into an instrument of white supremacy.”

Yet, on Princeton’s campus sits the Woodrow Wilson School of Public Policy and International Affairs, a residential college bearing his name and a dining hall festooned with a mural of him.

Anson’s page on the baseball Hall of Fame’s website is, of course, fawning. It even includes this observation from former Hall historian Lee Allen: “For years [Anson] stood at first base for Chicago like a might oak. Sturdy, blunt, and honest . . . The captain who was always kicking at decisions, the symbol of all that was strong and good in baseball.”

Only if you click on an entry on the side under the heading “Did You Know/There’s more info at the SABR Bio Project,” and read well down into the extensive biography, do you get the full measure of Anson.

“Regrettably, Anson used his stature to drive minority players from the game,” wrote Society for American Baseball Research historian David Fleitz. “An 1883 exhibition game in Toledo, Ohio, between the local team and the White Stockings nearly ended before it began when Anson angrily refused to take the field against Toledo’s African-American catcher, Moses Fleetwood Walker. Faced with the loss of gate receipts, Anson relented after a loud protest, but his bellicose attitude made Anson, wittingly or not, the acknowledged leader of the segregation forces already at work in the game. Other players and managers followed Anson’s lead, and similar incidents occurred with regularity for the rest of the decade. In 1887, Anson made headlines again when he refused to play an exhibition in Newark unless the local club removed its African-American battery, catcher Walker and pitcher George Stovey, from the field. Teams and leagues began to bar minorities from participation, and by the early 1890s, no black players remained in the professional ranks.”

Moses Fleetwood Walker was the first black major leaguer. Anson’s protest made him the last until Jackie Robinson, whom baseball in the past 20 years turned into a cause for celebration with little castigation of its role in Robinson getting an opportunity to play baseball only as a racial guinea pig.

Princeton president Christopher L. Eisgruber stated last month that the university would be open to the possibility of renaming the Wilson School and removing the dining hall mural of Wilson. Baseball doesn’t have an award named after Anson that black players he abhorred could win. His mustachioed face doesn’t loom over any major league parks.

But in a time when we as a nation are — with a hat tip in particular to student demonstrators on college campuses across the country — correcting offensive iconography, baseball should be proactive, especially given its expressed concerns about dwindling numbers of black kids from the U.S. pursuing its game.

I first became aware of Anson’s inglorious role while reading Jules Tygiel’s “Baseball’s Great Experiment: Jackie Robinson and His Legacy” when it came out in the early ‘80s, and my reaction wasn’t to have Anson removed from the Hall as unworthy. I don’t feel that way now, either.

But I don’t think anyone has had a greater impact on baseball than Anson, and he is not acknowledged as having done so on his plaque.

A Hall executive reminded me the other day that the Hall doesn’t want to engage in revisionist history. But in 2008, the hall amended the plaque of one of its most famous inductees — Robinson, of all people.

From 1962 until then, Robinson’s plaque, at his wishes, reflected only the statistical and awards that highlighted his career. “LEADING N.L. BATTER IN 1949. HOLDS FIELDING MARK FOR SECOND BASEMAN PLAYING IN 150 OR MORE GAMES WITH .992. LED N.L. IN STOLEN BASES IN 1947 AND 1949. MOST VALUABLE PLAYER IN 1949. LIFETIME BATTING AVERAGE .311. JOINT RECORD HOLDER FOR MOST DOUBLE PLAYS BY SECOND BASEMAN, 137 IN 1951. LED SECOND BASEMAN IN DOUBLE PLAYS 1949-50-51-52.”

But for the past seven years, the edited script on his plaque included this final line: “DISPLAYED TREMENDOUS COURAGE AND POISE IN 1947 WHEN HE INTEGRATED THE MODERN MAJOR LEAGUES IN THE FACE OF INTENSE ADVERSITY.”

It is long past time for a final line to be added to Anson’s plaque. After all, Anson started what Robinson is lauded for taking the chance to end.

Kevin B. Blackistone, ESPN panelist and visiting professor at the Philip Merrill College of Journalism at the University of Maryland, writes sports commentary for the Post.