Baltimore isn’t exactly a country town, at least not on paper. So why are Orioles fans so proud to be country?

For decades, that question has fallen by the wayside nightly, as O's fans lean into tradition and belt out the lyrics to John Denver’s 1975 hit “Thank God I’m a Country Boy” during the seventh-inning stretch of Orioles home games, first at Memorial Stadium and now at Oriole Park at Camden Yards. It is a tradition like few other in baseball, the kind that’s existed for so long it’s past the point of needing to make sense.

If you ever wondered why “Take Me Out To The Ballgame” isn’t enough in Baltimore, you aren’t alone.

The answer is simple: tradition. A catchy song caught on, and then became the norm. It’s now ingrained deep in the Oriole Park experience, and remains there to stay.

But how did it begin?

According to legend, longtime Orioles shortstop Mark Belanger was the first to suggest “Country Boy” to general manager Frank Cashen, who, by the summer of 1975, was looking to infuse more contemporary music into the fan experience at Memorial Stadium. “Thank God I’m a Country Boy” was a No. 1 hit, reaching the top spot on both the Billboard Hot 100 and Billboard Hot Country chart that summer. The song beta tested better than any other the O's had tried out in that season, which ended in a disappointing second-half finish after consecutive American League East titles.

By 1976, “Thank God I’m a Country Boy” had done what catchy songs do: it nested in the ears of the people who listened to it all the time and took root. One night, as a way to kill time on the bench, three Orioles -- Doug DeCinces, Tim Nordbrook and Tony Muser -- formed a pantomime band and put on a pretend performance during the seventh-inning stretch. They turned baseball equipment into air guitars, fiddles and microphones, to the delight of the scoreboard cameras that caught the act on film.

It became a thing. Soon, the three were “performing” most nights, until one night, when the O’s were trailing in a tense one-run game, they stopped. It did not feel like the time for goofing around. But that was when the famously superstitious Earl Weaver chastised the trio for not playing. The way Weaver saw it, Denver's hit brought the Birds important mojo.

Recalling the story to author Dan Connolly for the 2015 book “100 Things Orioles Fans Should Know and Do Before They Die,” DeCinces remembered Weaver barking: “‘What the hell are you doing? Get your s*** ready!’”

“That’s exactly what he said,” DeCinces recalled. “Weaver was so superstitious, and we’d been doing it for a while, and so all of a sudden, Earl wanted it. … From that point on, we did it the rest of the year.”

The “Country Boy” craze peaked at the 1983 World Series, when Denver attended and performed the national anthem before Game 1 of the Fall Classic against the Phillies. During the seventh-inning stretch that night, Denver sang “Thank God I'm a Country Boy” from the top of the Orioles dugout, to great fanfare. The O's would go on to win the Series in five games.

Returning to Baltimore for a benefit concert in 1997, Denver made a surprise appearance at Camden Yards that September, three weeks before his death. In interviews over the years, Denver always cherished his connection to the city and the Orioles fanbase, however random it may have been.

The Orioles have tried to implement new seventh-inning stretch music over the years: “Orioles Magic” in 1980, Rick Dempsey’s “Old Time Rock and Roll” cover in ’87, and others. None caught on like Denver's “Country Boy,” though the song was taken out of circulation from '88-93 by owner Eli Jacobs. It returned after Peter Angelos bought the team and remains to this day, played immediately after “Take Me Out To The Ballgame.”

It’s been that way for roughly 40 years. Some things never change.