To the Tune of...

"''"The Red Flag": nice tune, shame about the words.""

So you've got some lyrics. They're wonderful, they're catchy, but you just can't seem to come up with the right music...

Hey, why not just put it to the tune of an older song?

One of The Oldest Ones in the Book, as many, many traditional songs and national anthems do this. This can produce a very dissonant effect if the two songs have completely different moods. It's also common in hymnody; most traditional hymnals include the meter signature for each text so it can be easily matched to other tunes; e.g., Common Meter (8.6.8.6 -- used by Amazing Freaking Grace and many others).

See also Suspiciously Similar Song. Sampled Up is when this version completely eclipses the original. Filk Songs are sometimes set to the tune of existing songs.

Film

 * In the 1988 comedy Moon over Parador, the new president changes the national anthem to "Parador, te amo" ("I love you, Parador"), which goes to the tune of "Bésame Mucho". Sammy Davis Jr. sings it.

Live-Action TV

 * Community episode "Comparative Religion" ends with the group performing an inclusive, secularized rewrite of "Silent Night". (Sensible night, appropriate night / Snow on ground, left and right...)
 * Monty Python's "The Lumberjack Song" and the older The Goon Show song "Ying Tong Song" both use very similar arrangements to Eddie Morton's "I'm a Member of the Midnight Crew", which was long out of print when the two shows came along. (You might recognize it from it being referenced in Homestuck.)
 * In Doctor Who, the Third Doctor sings a "Venusian lullaby" to a monster (specifically, the Monster of Peladon) that somehow has the same tune as "God Rest Ye Merry, Gentlemen."

Theatre

 * Entire genres of theatre work under this principle. For instance, "ballad operas"—the most famous probably being John Gay's The Beggars Opera—took popular tunes and rewrote their lyrics to tell a story. (Note, though, that Weill and Brecht's adaptation of The Beggar's Opera, The Threepenny Opera, had original music, except for the "Morning Anthem", which reused one of the 18th-century tunes.) The genres of "burlesque", "extravaganza" and a few others were the same. Most of these genres are completely or near-completely dead, except for British pantomimes (a sort of very silly Christmas show, with crossdressing and audience participation), which appear every year in Britain.
 * Also, if composers borrowing their own work counts, almost all of Händel's operas, cantatas and oratorios borrowed music from himself or even adapted from other composers, in varying amounts.

Web Comics

 * The song sung by the Easter Bunny in Sluggy Freelance is not-so-subtly modified from Monty Python's Lumberjack song.
 * Which in turn is based on one of Wolfgang Amadeus Mozart's operatic arias.
 * In The Order of the Stick #445 (titled A Song for the Departed), Elan sings a song which is told in a note that it's sung to the tune of "O Danny Boy". Warning, spoilers!

Western Animation

 * Family Guy did this several times. The tune for "The FCC Song" is from Take Me Along, an old Broadway musical. The tune for "A Bag of Weed" is from Chitty Chitty Bang Bang. Whether a given song from the show counts as this trope or straight-up parody mostly depends on how obscure the originals were.
 * One of the cases on Harvey Birdman, Attorney at Law consisted of him prosecuting for a Japanese band called Shoyu Weenie, who were accusing the Neptunes (yes, from Jabberjaw) of stealing their hit.
 * The Simpsons -- "O Whacking Day" is strong Lyrical Dissonance for Americans and Germans familiar with the yuletide hymn "O Christmas Tree", less so for Britons who know the bloodthirsty lyrics of the revolutionary hymn of the same tune.
 * The Totally Spies! Theme Tune uses the tune of the rather obscure song "Here We Go" by Moonbaby.

Real Life
""It was such a clichéd riff. It was so close to a Boston riff of 'Louie Louie'.""
 * The former Trope Namer is "God Save the King/God Save the Queen," sung in America as "My Country, 'Tis of Thee" and in Imperial Germany as "Heil dir im Siegerskranz."
 * Even funnier, one of the first Russian national anthems was this British anthem with new lyrics in Russian. But soon the British Empire became the rival to the Russian Empire, and Russians wrote their own anthem with their own tune ("Spasi bozhe tsarya khrani"), that survived until the revolution.
 * And after the revolution, things got even funnier. The Soviet anthem "Soyuz Nerushimy" (The Unbreakable Union) was originally, before WWII, an anthem of the Communist Party, with different lyrics. After Stalin died, the lyrics were at first totally removed under Khrushchev, and under Brezhnev the anthem received new lyrics, particularly changing the second stanza that hailed Stalin, and totally removed the third stanza that emphasized the military. And the current Russian anthem is basically Soyuz Nerushimy with lyrics changed once more again, now removing all references to Lenin and communism and replacing them with your garden variety patriotic lyrics.
 * The temporary Soviet anthem and worldwide Communist song "The Internationale" was originally sung to "The Marseillaise".
 * Communists in several Latin-American countries still sing it that way.
 * Bunches of national and state anthems fit this trope. The American national anthem, for example, is a poem by Francis Scott Key set to the tune of the English drinking song "To Anacreon in Heaven."
 * The modern version doesn't sound much like a drinking song because John Philips Sousa altered the tempo to make it sound more dignified. Modern people familiar with the Sousa arrangement might be quite surprised by earlier, jauntier versions.
 * Possibly Older Than They Think: the initial version of the theme was allegedly written by Jean-Baptiste Lully for the King of France Louis XIV, then plagiarised by Händel, who sold it to the British crown.
 * The national anthem of Liechtenstein is sung to the same tune. Hilarity Ensues when England play Liechtenstein in football.
 * And somehow somewhere in the mists of time since Lully and Händel, the tune entered Swedish folk music, where the key was changed to minor (Swedish folk music is nearly always in minor key). So in Sweden, it's a sad little song on how it's actually better to be abandoned than to be locked in a marriage with someone who doesn't love you, even if both of them suck.
 * The first Korean national anthem was originally a traditional Korean poem sung to the tune of Auld Lang Syne.
 * O Canada, the Canadian national anthem, was originally a patriotic French-Canadian poem set to music for a Saint-Jean-Baptiste Day ceremony. The English lyrics were written much later and do not constitute a literal translation. (Ironically, this is now the one song you are probably least likely to hear in Québec on Saint-Jean-Baptiste Day, due to that holiday's strong association with the sovereignist movement.)
 * In a case legally ruled to be plagiarism, "Hail! Hail! The Gang's All Here" appropriated the tune of "With Catlike Tread" from The Pirates of Penzance.
 * The tune itself is a reference to "The Anvil Chorus" from Il Trovatore. Listen to the "Come, friends who plough the sea" bit.
 * Similarly, George Harrison's My Sweet Lord was ruled to have plagiarized the Chiffons' He's So Fine, in a case of what the judge called "unconscious copying". Harrison later bought the rights to the song to avoid further legal entanglements.
 * It is worth bearing in mind that Renaissance composers such as Josquin, Ockeghem and Dufay who created the foundations of our musical language worked almost EXCLUSIVELY with melodies that were not their own. Many of their works were even called "parody masses", in the sense that they used short pieces of music (not just a melody) composed by others as a starting point. (Parody does not imply a humorous appropriation in this case).
 * A good number of songs written early on for Barney and Friends, including the theme song and I Love You, are set to the tune of traditional kids' songs. The show, however, has a ton of original songs as well, even in its early days.
 * "Twinkle twinkle, little star..." / "A B C D E F G..." And they're all based on the French song "Ah vous dirai-je, Maman"—which itself inspired a 13-part Mozart piece. (There should be 11 more links, but Wikipedia don't have 'em. Oh, well!)
 * Germans know this one as "Morgen kommt der Weihnachtsmann" ("Tomorrow comes Santa"—a Christmas song!)
 * Finnish children learn both the ABC song and the star song (called "Tuiki tuiki tähtönen"). There was a third song to the same tune, "Lapsukaisten koululaulu" (starting with "koska meitä käsketään"). It's been pretty much forgotten about, probably because it's basically propaganda of 50's values.
 * In Dutch it's "Altijd is Kortjakje ziek" (about a girl who's always sick on weekdays buy well on Sundays).
 * Coldplay have been accused of doing this with their song "Viva la Vida" (which, itself, is about a king), being accused of copying the melody from four different sources: alternative rock band Creaky Boards (who retracted the claim and decided that both bands probably stole the tune from The Legend of Zelda), guitar virtuoso Joe Satriani's "If I Could Fly," and Cat Stevens' "Foreigner" suite. And "Talk" borrows ITS main riff and parts of ITS melody from Kraftwerk's "Computer Love"—though they sought permission before releasing it, and the members of Kraftwerk are credited with co-writing the song.
 * On the topic of "Viva la Vida", there's more than that, actually. The above three are the most well known because they were the only 3 to accuse Coldplay of plagiarism. There's actually more things that sound similar to Viva la Vida, like Francis Limon, Ding Dong Song, J'en Ai Marre, Hearts, and Dirty Diaper Blues. Or at least that's what this video is saying. And there may be more. And there may be similar sounding songs made after Viva la Vida. Someone should make a medley based on that single melody and its variations.
 * Mitch Benn wrote a song, referencing his earlier "Everything Sounds Like Coldplay Now" about new bands copying Coldplay's style, called "Now Coldplay Sound Like Everything Else" (to the tune of 'Viva la Vida'.)
 * As pointed out in Mr. Holland's Opus, "A Lover's Concerto" by The Toys uses the sweet strains of Johann Sebastian Bach's "Minuet in G" stretched to four-quarter time.
 * A huge number of Elvis Presley's hits were new lyrics written for old music. "It's Now or Never" is a cover of the 1898 Neapolitan aria "O sole mio". "Can't Help Falling in Love" uses a melody from 1780. "Love Me Tender" is a version of "Aura Lee", written in 1861. "There's No Tomorrow" is another.
 * "Danny Boy" is only one of many lyrics written for the tune of "Londonderry Air." Just try to explain the "simple" progression here: The theme to the anime Romeo X Juliet is "Inori~You Raise Me Up〜" sung by Lena Park. That was a take-off of "You Raise Me Up" by Rolf Løvland of Secret Garden. This was taken from "Danny Boy", which is, in turn, set to the tune of "Londonderry Air".
 * Bright Eyes' "Road To Joy", as the title hints, takes ITS melody from Beethoven's "Ode To Joy".
 * A related phenomenon: Jazz compositions often consist of new melodies laid over the chord changes of some standard. "Hot House" (based on Cole Porter's "What Is This Thing Called Love?") may be the most famous example.
 * Edward Elgar's Pomp and Circumstance March No. 1, composed in 1901, was almost immediately given words to turn it into the patriotic hymn Land of Hope and Glory for King Edward VII's coronation in 1902. In the US, it is still often performed without the lyric, most often at school graduations.
 * "My Way," most famously performed by Frank Sinatra, is set to the tune of a French song, "Comme d'habitude."
 * Michael Jackson was accused of doing this with "Will You Be There", apparently set to the tune of a song by Italian singer Al Bano. Italian courts eventually ruled in favor of Jackson. Bano had to pay Jackson's legal fees. The song does start with a snippet of Beethoven's 9th Symphony, however (and this Jackson also got in trouble for as initial releases lacked the proper credit; this was promptly fixed.)
 * Germany's national anthem uses a tune that was originally written by Joseph Haydn for Francis II of the Holy Roman Empire. The tune is also used for several hymns. Most Americans probably associate the song exclusively with World War Two, but it's Older Than They Think.
 * "This Land Is Your Land", by Woody Guthrie is from the traditional folk song "Oh, My Loving Brother"
 * The Red Hot Chili Peppers were accused of ripping off Tom Petty's "Mary Jane's Last Dance" with their own "Dani California".
 * Nirvana were accused of copying the bass riff from "Eighties" by Killing Joke for their song "Come as You Are".
 * Kurt Cobain admitted that with "Smells Like Teen Spirit" he was trying to write a Pixies song, and the end result sounds quite a bit like their song "U-Mass" in terms of overall sound and "Debaser" in terms of the main riff. And then when the song came out non-alt rock people thought it sounded like "More Than a Feeling", which he was also aware of:


 * "Alouette" = "Down By the Station"
 * The hymn I Vow to Thee My Country takes its tune from "Jupiter" in Holst's Planets suite.
 * "I Fear IKEA" by The Lancashire Hotpots is sung to the tune of "The Wild Rover". ("That's why I fear IKEA (clap-clap-clap-clap) I won't go there again! I don't want a bookcase called Billy, or a table called Sven!")
 * Others include "Bitter Lager Cider Ale Stout" (to the tune of "She'll Be Coming Round the Mountain") and "Dolby 5.1" (to The Jimmy Hart Version of "Matchstalk Men and Matchstalk Cats and Dogs").
 * Actually most Hotpots songs. Some aren't quite so obvious to people without a folk music background, though.
 * On another note, when hearing The Wild Rover's chorus for the first time, most Germans start singing An der Nordseeküste (At the north sea's coast), a silly song by silly East Frisian singers Klaus & Klaus.
 * The University of Texas' school song, "The Eyes of Texas", is set to "I've Been Working on the Railroad".
 * The Alma Mater Song of Yale is a taken from German patriotic hymn "The Watch on the Rhine", best known in America for its appearance in the "Marseillaise" scene in Casablanca
 * "The Red Flag" was not originally intended to be "O Christmas Tree". For example: "Our Christmas tree is deepest red / it's shrouded of our martyred dead / and ere its limbs grew stiff and cold / our heart's blood dyed to every fold / so raise the scarlet standard high / beneath it's shade we'll live and die / though cowards flinch and traitors sneer / we'll keep the red flag flying here."
 * "O Christmas Tree" was originally in German, as "O Tannenbaum", which means pretty much the same thing—okay, literally, it's "O fir-tree," but what, you were expecting maybe a Christmas maple?
 * And of course "The Red Flag" has been parodied, thanks to New Labour, as "The People's Flag Is Palest Pink."
 * Maryland, Florida and Iowa have all adopted the melody for a state song at some point.
 * Pet Shop Boys' "It's a Sin" was alleged by the 80s DJ Jonathan King to have plagiarised Cat Stevens' "Wild World" and remixed Stevens' vocals to the PSB version onto a single (see the George Harrison case above; it was the B-Side to this single). The funny thing is that Stevens' version actually sounds a lot more like "It's a Sin" than King's version.
 * The Kinks' "Catch Me Now I'm Falling" has a guitar riff similar to The Rolling Stones' "Jumpin' Jack Flash", while the ending of "U.K. Jive" recalls The Who's "My Generation".
 * The Who's "I Can't Explain" has a similar feel and guitar tone to The Kinks' "You Really Got Me". Both were produced by Shel Talmy, and Townshend himself admitted "Explain" was written as a Kinks ripoff. The Clash later used the riff from "I Can't Explain" twice, once for "Clash City Rockers" and again for "Guns On The Roof".
 * As does The Doors' "Hello, I Love You" to "All Day and All of the Night."
 * Bruce Springsteen's "Outlaw Pete" has a similar melody to Kiss' disco single, "I Was Made For Lovin' You".
 * The Boss is a phenomenal songwriter otherwise, but Radio Nowhere is essentially 867-5309 made heavier and more awesome.
 * Mägo de Oz, a Spanish Power Metal/Folk Metal band, is very prone to this. As an example, they have a song, "En Nombre De Dios", which is basically "The Gates of Babylon" by Rainbow + new lyrics about the Corrupt Church.
 * Radiohead's "Karma Police" uses piano passages that are lifted almost verbatim from the Beatles' "Sexy Sadie".
 * The famous "Habanera" from Bizet's Carmen was based on what the composer originally thought to be a folk melody, but turned out to be a composition of a contemporary Spanish musician Sebastian Iradier called "El Arreglito". Bizet acknowledged this in the score. Of course, Bizet's version is a vast improvement.
 * The Japanese children's song "Musunde, Hiraite" and "Go Tell Aunt Rhody" are both based on the Pantomime of Jean-Jacques Rousseau's opera Le Devin du Village.
 * The well-known "Oh, Where, Oh, Where Has My Little Dog Gone?" was originally a comedy song called "Der Deitcher's Dog" [sic] about how the eponymous German's dog has been made into sausages—itself stolen from a Swabian folk song, Zu Lauterbach hab i mei Strumpf verlorn.
 * Australian courts ruled that the flute riff in Men at Work's hit "Down Under" is a straight rip off of the tune to nursery rhyme "Kookaburra Sits in the Old Gum Tree".
 * "The Arkansas Traveler", "Bringing Home a Baby Bumble Bee", and "Peanut Butter Sandwich".
 * "Turkey in the Straw" (verse), and "Do Your Ears Hang Low". Also the Doughnut Shop song. And the Animaniacs state capitals song. One of the earliest incarnations of this tune was the minstrel song "Zip Coon."
 * "Have You Ever Seen a Lassie" and "The More We Get Together".
 * "The Itsy Bitsy Spider", "Sweetly Sings the Donkey", and "Ten Green Bottles".
 * "Johnny Comes Marching Home", "The Ants Came Marching" and "Ghost Riders in the Sky" all were based on the Irish ballad Johnny I Hardly Knew Ye
 * The satirical Taisho-era Japanese song "Tokyo Bushi" (often called "Pai-no-pai-no-pai" for its nonsensical chorus) took its melody from an American Civil War marching song, "Marching Through Georgia".
 * Cherry's "Yes I Will" uses the tune of P!nk's "U & Ur Hand" ad verbatim.
 * "This Little Light of Mine", and "Worried Man Blues".
 * Patsy Gallant gave us "From L.A. to New York", to the tune of Québecois folk song "Mon pays". The English lyrics (written by Gene Williams) are nothing at all like the French lyrics, and the original author (Gilles Vigneault) has disowned the English version. (to be fair, Mlle. Gallant also recorded the French version in the same disco style)
 * The martial, patriotic marching song "The British Grenadiers" is to the tune of a seventeenth-century comic song called "The New Bath".
 * All over the place in just about any hymnal:
 * The hymns "For the Beauty of the Earth" and "As with Gladness Men of Old" both use "Dix", a melody composed by Conrad Kocher.
 * "What Child Is This," a Christmas song, was written with the melody from "Greensleeves", an English folk song.
 * Likewise, the hymn "Lord of the Dance" copied "Simple Gifts", a Quaker song.
 * The traditional Gaelic hymn tune "Bunessan" has been used for the Christmas carol "Child in a Manger" and more commonly for the hymn "Morning Has Broken".
 * "Battle Hymn of the Republic" comes from "John Brown's Body", as does "Oil Thigh," the Football Fight Song of Queen's University.
 * In turn, the union hymn "Solidarity Forever" used the same tune.
 * Overall it's a common practice for even new lyricists to repurpose existing familiar tunes for new hymns.
 * When the (Liverpool) Spinners performed the folk song "Old Johnny Booker" they got one woman complaining that the song was "sacrilegious" because it has the same tune as her favourite hymn. What she didn't realise is that both the hymn and the folk song lifted the tune from an earlier song.
 * The tune "Winchester Old"; best known as the UK tune for "While Shepherds Watched Their Flocks by Night", but also the tune of several other hymns (and nearly the same as "There Is A Green Hill Far Away").
 * Really, you could pick up any two hymnals at random and find that they have totally different melodies for the same words. The fact that a lot of hymns are in Common Meter really helps.
 * "I Saw Three Ships" and "Here We Go Round the Mulberry Bush".
 * "For He's A Jolly Good Fellow" AKA "The Bear Went Over The Mountain" AKA "We Won't Get Home Until Morning" is known in French as "Marlborough s'en va en guerre."
 * When Billy Joel wrote "Uptown Girl", he in part (accidentally) plagiarised a Mozart piece.
 * Baracuda did this with using the tune from Amaranth by Nightwish, and the lyrics to "Where Is the Love?" by Alice Cooper. This can be seen here.
 * The Roman Catholic Liturgy does this to itself. "The Mystery of Faith" and "The Great Amen" are generally sung to the same tune (assuming, of course, that they are sung).
 * Metallica's "The Unforgiven II" sounds almost exactly like "Children of the Damned" by Iron Maiden (which itself resembles "Simple Man by Lynyrd Skynyrd)
 * "Frere Jacques", "Where is Thumbkin", and the Chinese children's song "Liang Ji Lao Hu." ("Two Tigers")
 * "(There was an Old Man named) Michael Finnegan", "Ten Little Indians", and "Paw Paw Patch."
 * "The Farmer in the Dell" and "A Hunting We Will Go."
 * "Mary Had a Little Lamb" and "Merrily We Roll Along."
 * "Lightly Row" and the Chinese children's song "Xiao Mi Feng." (The Little Bee)
 * "Minuet in G" and "A Love Concerto."
 * "The Modern Major General's Song" and "The Elements Song."
 * "The Mexican Hat Dance" and "Yakko's World."
 * "Dem Bones (Dem Dry Bones)" and "Sally the Camel."
 * "BINGO (Was His Name-O)" and the opening theme to Camp Lazlo.
 * "Orpheus in the Underworld (Can-Can)" and the theme to Fighting Foodons.
 * "A Tisket, a Tasket (A Green and Yellow Basket)", "Rain, Rain, Go Away", and "It's Raining, It's Pouring (The Old Man is Snoring)."
 * "When Johnny Comes Marching Home Again" and "The Ants Go Marching."
 * "99 Bottles of Beer on the Wall" and "The Planet Song."
 * "Aiken Drum" and "Let's Name the Species of the Open Sea."
 * "The Syncopated Clock" and "One of These Things is Not Like The Others."
 * "Dives and Lazarus", "The Star of the County Down", "Gilderoy", "The Thresher", "Crooked Jack", "The Unquiet Grave", "The Fighting 69th", "The Murder of Maria Marten", "Baledwyr Nefyn", "O sing a song of Bethlehem", "I heard the voice of Jesus", "If You Could Hie to Kolob" (Mormon), "When Jesus Walked Upon This Earth" (Quaker), and "The Year Turns Round Again" from War Horse.

Sports

 * Just about every Australian Football League club theme song is an existing song with rewritten lyrics, as can be seen here. The only exceptions are Fremantle (which includes a small section from "Song of the Volga Boatmen"), Port Adelaide and West Coast.
 * The Perth Wildcats' anthem is to the tune of the "Hallelujah Chorus".