The Fenway crowd arrived early for the fifth game of the 1918 World Series, but by mid-afternoon the only thing moving on the field was the clock. The players were on strike beneath the stands, protesting deep cuts to postseason pay.

To frustrated fans who had shelled out good money — $3 plus a 30-cent war tax for box seats — the merits of the argument mattered little. When the Sox and Cubs relented and took the field, some fans stung them with catcalls about socialism and shirked duty.

Then a small band on the first base side struck up “The Star-Spangled Banner,’’ without amplification. A hush fell over Fenway, as thousands of men removed their hats and stood solemnly, openly moved.

Some have pointed mistakenly to that moment as the first playing of the anthem before a World Series game and as a starting point for a sustained tradition that continued Tuesday night, as the Fall Classic got underway in Los Angeles.

While that assertion is not entirely accurate, the playing of the anthem multiple times in the 1918 World Series — better remembered here for producing the third Red Sox championship in four years, before an 86-year drought — generated national headlines and helped cement the relationship between the song and spectator sports.

And it’s a moment worth examining amid the charged climate today, with a national debate — fanned by the president and persisting through each week of the NFL season — over the propriety of protest while the anthem is being played before games.

Amid a surge of patriotism and undercurrent of nativism, newspapers during World War I regularly carried stories featuring “The Star-Spangled Banner’’ as an emblem of unity and fortitude — civilians singing it while surviving a German U-boat attack on a steamship, for example — while noting the frequent beatings and even arrests of people who failed to stand for the anthem in theaters, parks, and other public spaces.

Just a week before the 1918 World Series, hundreds of thousands — possibly millions — of Americans in all 48 states joined in the latest government-encouraged “Liberty Sing,’’ pausing for a simultaneous 9 p.m. Eastern time rendition of “The Star-Spangled Banner’’ that rose from Philadelphia’s Independence Square and Boston Common, and from venues as varied as hospital wards, newspaper composing rooms, and city council chambers.

Though Congress would not formally recognize “The Star-Spangled Banner’’ as the national anthem until 1931, by wartime the song was already widely referred to as such, carrying expectations of hat removal and standing.

At the same time, baseball was struggling for relevance in 1918 after falling on the wrong side of a federal “Work or Fight’’ order, requiring draft-age men to enlist, find jobs in essential industries, or face conscription.

Scrambling to avoid the financial bath of an abrupt cancellation, the major leagues negotiated with the federal government to grant ballplayers an extension, allowing for a shortened season followed by a September World Series. As per-game attendance dwindled anyway, owners draped their parks in patriotic fanfare, including regular “preparedness’’ demonstrations, with players marching in game uniforms.

Enter the anthem, amid the same spirit that saw Boston invite scores of wounded soldiers to home games at the World Series.

In Chicago, the stands at bunting-draped Comiskey Park — borrowed by the Cubs — were sparse and the crowd muted for Game 1 on Sept. 5, amid added anxiety over a bombing the day before at the city’s federal building. Then a 12-piece brass band played “The Star-Spangled Banner’’ during the seventh-inning stretch.

The result was so stirring that The New York Times led its recap with a paean to the moment, burying the first mention of the game itself (a 1-0 shutout by Sox pitcher Babe Ruth).

“Far different from any incident that has ever occurred in the history of baseball was the great moment of the first world’s series game between the Chicago Cubs and the Boston Red Sox, which came at Comiskey Park this afternoon during the seventh-inning stretch,’’ the story began.

“The yawn was checked and heads were bared as the ball players turned quickly about and faced the music. . . . First the song was taken up by a few, then others joined, and when the final notes came, a great volume of melody rolled across the field.’’

That passage tripped later historians into thinking the anthem was a first, at a time when evidence to the contrary remained hidden in microfilm or on moldering paper. A second reading suggests it was actually the crowd’s unified singing — ending with a surprise burst of applause — that struck the writer.

The Cubs had already played the anthem during the seventh inning on scattered occasions.But in his landmark 1974 biography of Babe Ruth, Robert Creamer cited the Game 1 rendition of the anthem as the origin of “a long-standing baseball tradition,’’ noting that Chicago repeated it in the seventh inning of Games 2 and 3 before the series shifted to Boston, where Sox owner and Broadway producer Harry Frazee moved the song to the start.

“Thereafter it was usually played on opening day and at World Series games and other special occasions that warranted the presence of a band,’’ Creamer wrote, becoming an every-game phenomenon with the spread of sound systems and another wave of patriotism in World War II.

Many writers repeated that account, including multiple publications this year. Others unearthed earlier pairings of the anthem and baseball, establishing that major league teams often played it on Opening Day and the Fourth of July by the early 20th century.

A Globe review found numerous reports of the anthem being played at earlier World Series, including twice in Game 2 of the 1915 Sox-Phillies series, once when the band mistook the entourage around the mayor of Philadelphia for the pregame arrival of President Wilson, and once in the ninth, when the president helped lead the singing. (When Wilson actually arrived, the band was taking a break.)

The difference in 1918 was the war, which elevated the anthem from passing reference to headline. And the coverage of Game 5 in Boston suggests less a planned pregame anthem than an unexpected rendition, with power to suddenly soothe an unsettled crowd.

Days earlier, players had been outraged to learn they would be receiving vastly reduced World Series bonuses, with management giving them a smaller percentage than usual from a pool of ticket sales that were already down.

When the players tried to advocate for themselves, the three-member National Commission that oversaw baseball rebuffed them. So the players refused to suit up for Game 5, triggering emergency negotiations.

With management unyielding, the ballplayers relented — provided they could make a statement that they were playing under protest for the “sake of baseball’’ and public enjoyment.

“The truth of the matter is, they were being given a rotten deal,’’ but fans in that moment had little interest in picking sides in a financial squabble over a game played during wartime, said Richard A. Johnson, curator of The Sports Museum of New England and coauthor of “Red Sox Century,’’ a history of the team’s first 100 years.

Newspaper accounts that day varied widely, but a Boston Post cartoon showed a flock of angry fans crying out for the game to start and threatening to leave.

The Boston Evening Globe described the crowd as placated largely by the “heroic work’’ of an exhausted band filling time with song after song. One wire account praised that band’s “touching’’ performance of “Don’t Bite the Hand That’s Feeding You,’’ a love-it-or-leave-it number instructing immigrants who disrespect “Uncle Sammy’’ to “go back to your home o’er the sea.’’ Several highlighted the playing of the wartime hit “Over There,’’ as a group of wounded soldiers made their way through the grandstand on crutches.

But when the players appeared and cursory news about the strike spread, some fans excoriated them as “ ‘Bolsheviki’ and ‘shameless holdups’ and a lot of other names which would not look nice in print or have been pleasant to have been heard by those to whom these terms applied,’’ the Evening Globe wrote.

Then the first notes of “The Star-Spangled Banner’’ sounded. “The band did not blare out the anthem as is customary,’’ an account in New York’s Middletown Times-Press said. “It played it softly, and in the presence of those boy heroes who have given their lives over to blight and disease for their country, it seemed like the benediction of prayer.’’

The Sox lost 3-0, and the crowd dropped sharply the next day, with Fenway less than half full to witness the Sox clinch their fifth championship. Some of the loss was likely due to it coinciding with the latest Registration Day, requiring men not included in earlier Selective Service calls to register in person. But many sportswriters attributed it to frustration over the bonus-pay dispute, calling it a black eye for a game about to go on hiatus for a war that might last into the 1920s.

Instead, Germany surrendered in November, and baseball returned in 1919. The next World Series — defined for posterity by the Black Sox gambling conspiracy — began with the anthem.

Eric Moskowitz can be reached at eric.moskowitz@globe.com. Follow him on Twitter @GlobeMoskowitz.