Glenn Miller and His Orchestra topped the American pop charts with the ebullient "In the Mood" as war raged overseas on this day in history, Feb. 10, 1940.
His most famous song, along with other iconic hits, made Miller the biggest bandleader of his era and provided the swinging soundtrack of the Greatest Generation during World War II.
"Miller is the sound of the boys fighting overseas, especially as he went overseas himself," Jordan Runtagh, host and producer of pop-culture podcast "Too Much Information" on iHeartRadio, told Fox News Digital.
"'In the Mood' is a song that transcends music. If you want to evoke that era, if you want to hear the sound of America in World War II, you put on that song."
"In the Mood" and other Miller tunes were also major hits in the United Kingdom during the war years.
Miller died in service of the U.S. Army in a plane crash flying from London to newly liberated Paris on Dec. 15, 1944. He was 40 years old.
His body was never found, fueling conspiracy theories that linger to this day.
Miller's wartime death cemented his eternal connection with the era.
"The bespectacled, tight-lipped bandleader seemed more like the leader of a choir than a swing band, but his keen arranging skills and ear for melody ensured that at least every other tune he recorded seemed like the anthem of the age," wrote AllAboutJazz.com in a review of Miller and "In the Mood."
"He was the most popular bandleader of his day."
KIRK CAMERON HEADS TO GEORGIA PUBLIC LIBRARY AMID ‘CRUMBLING’ MORALITY IN US: ‘PEOPLE NEED HOPE’
The infectious "In the Mood" boasts exuberant jazz clarinet and tenor sax duet, jitterbug beat and instantly recognizable opening notes.
It is etched in the annals of Americana.
Among other acclaims, "In the Mood" was added to the Library of Congress National Recording Registry in 2004 for songs that are "culturally, historically or aesthetically significant, and/or inform or reflect life in the United States."
"In the Mood" boasts 80 million plays today on Spotify, even though it was a hit nearly 70 years before the medium was even founded.
Miller and His Orchestra enjoyed massive popularity during the war years with other hits such as "Moonlight Serenade" and "Tuxedo Junction."
MEET THE AMERICAN WHO INSPIRED THE NATION IN TWO WORLD WARS: CHRISTIAN SOLDIER SGT. ALVIN YORK
Another of his wartime recordings, "Chattanooga Choo Choo," was the first gold record in U.S. music history.
A vinyl disc of the song was painted gold to celebrate its success as a publicity stunt — also on Feb. 10, in 1942.
"The record label, RCA Victor, celebrated by presenting Glenn Miller with a trophy during a live radio broadcast," NPR wrote online in 2017, noting that the song sold an incredible 1.2 million copies.
"Miller's honor started a self-congratulatory tradition of labels awarding their own artists framed gold records."
The name "gold record" stuck and was adopted as an official industry standard for 500,000 records sold in 1958.
Miller's energetic horns provided a soundtrack of positivity that put a swing in the step of the American people despite the daunting challenges and deaths of World War II.
"In the Mood" remains his most popular song.
It was, in many ways, the sound of the American heartland as its people fought for liberty across two vast oceans.
Alton Glenn Miller was born in Clarinda, Iowa, on March 1, 1904, but raised in Missouri and Nebraska before graduating from high school in Fort Morgan, Colorado, in 1921.
He briefly studied music at the University of Colorado.
He sought success in the music industry first in Los Angeles before finding it in New York City, working for big-band leader Tommy Dorsey before forming his own troupe.
Miller became a sensation in 1939, leading a concert at Glen Island Casino in New Rochelle, New York, that was broadcast over two national networks.
CLICK HERE TO SIGN UP FOR OUR LIFESTYLE NEWSLETTER
Miller was enlisted by Uncle Sam in the war effort in 1942. He was an active U.S. Army Air Forces officer, largely entertaining troops, when he was killed during the war.
"Almost from the moment the world learned Miller had gone missing, conspiracy theories began to emerge like puffs of smoke from the Chattanooga Choo Choo," the University of Colorado College of Music wrote in 2014 about one of its "most illustrious alumni."
Among the conspiracies: Miller died of a heart attack during a tryst in a Paris bordello, or was assassinated after secretly negotiating a truce with Hitler in Berlin.
Miller's plane, the story states, most likely crashed when fuel lines froze over the icy English Channel.
"The years haven't diminished the aura of eminence that Glenn Miller's band achieved here and abroad," musician and entertainment executive Mort Goode wrote in the liner notes of a 1974 two-record vinyl compilation, "The Complete Glenn Miller."
"'In the Mood' was clear evidence of Glenn Miller's solid and wise sense of commerciality. The song and arrangement had first been given to Artie Shaw … Miller cut it judiciously, built on the riff and made it an all-time masterpiece."