The "Happy Birthday" song, the most frequently sung piece of music on Earth, was originally written in 1893 by two American sisters as a kindergarten classroom greeting called "Good Morning to All" — and the birthday lyrics now sung at every party on the planet were added almost twenty years later by an unknown author

If two women in 19th-century Louisville had written essentially anything else — a nursery rhyme, a folk hymn, a marching band number, a parlour song — their names would today be remembered, if at all, by approximately the same audience that remembers the names of other 19th-century educational songwriters. Instead, they wrote a four-line classroom greeting that, through a sequence of unauthorised lyrical substitutions performed by unknown hands across the early 20th century, became the most frequently sung piece of music in the recorded history of the human species, generating an estimated billion or more individual performances per year — and the Hill sisters, Mildred Jane and Patty Smith of Louisville, Kentucky, remain almost entirely unknown to the billions of people who sing their composition annually. Mildred Jane Hill, the elder of the two, was a working musician — a concert pianist, organist, and composer, who specialised in the documentation and study of African-American musical traditions in late-19th-century Louisville and who became one of the first white American musicologists to argue, in print, that the blues and jazz traditions then emerging from Black American communities would eventually become defining genres of all-American music. She was correct. Patty Smith Hill, nine years younger, became the more publicly visible of the two sisters — a professor at Columbia University’s Teachers College for 30 years, a founder of the National Association for Nursery Education, the developer of the Patty Hill Blocks (a system of large-format wooden building blocks still used in American kindergartens today), and a substantial figure in the progressive education movement that established American kindergarten as a distinct educational stage.

According to the Songwriters Hall of Fame’s profile of the Hill sisters and the song they originally composed, the sisters began collaborating on children’s songs in approximately 1889, when Patty was developing the curriculum of the Louisville Experimental Kindergarten and Mildred was looking for compositional projects that combined her musical training with her sister’s pedagogical work. The collaboration produced more than a dozen songs across the early 1890s, all designed to be easy for young children to sing, all incorporating simple melodic intervals and repetitive lyrical structures suited to learners with limited prior musical exposure. “Good Morning to All” was the most successful of these compositions, in part because its function — a daily classroom greeting that could be used by any kindergarten teacher in any school — gave it a practical commercial application that the more elaborate compositions did not have. The sisters published it in 1893 in a songbook titled Song Stories for the Kindergarten, issued by the Chicago publisher Clayton F. Summy. The book went through more than 20 editions across the subsequent four decades. The sisters were honoured for their educational work at the 1893 Chicago World’s Fair the same year.

The unknown person who changed everything

The transformation of “Good Morning to All” into “Happy Birthday to You” occurred, by all available evidence, gradually and anonymously, between approximately 1900 and 1912, through a process that has never been documentarily traced to any specific individual. As detailed in Smithsonian Magazine’s reconstruction of the Hill sisters’ careers and the subsequent history of the song, the melody of “Good Morning to All” began appearing across the early 20th century in various American songbooks with modified lyrics. The first print appearance of the song with the now-familiar birthday lyrics was in 1912 — 19 years after the original composition — in a children’s songbook whose precise compiler the historical record has not preserved. The 1912 version did not credit any author for the new lyrics. It also did not credit the Hill sisters for the original melody. The combination of unattributed melody and unattributed new lyrics circulated for the next decade through various American songbooks and educational publications, none of which provide any documentary trail back to the specific individual who originally substituted “Happy birthday to you” for “Good morning to you” and “Happy birthday, dear (name)” for “Good morning, dear children.”

The professional copyright historian Robert Brauneis, who conducted the most comprehensive academic investigation of the song’s origins as part of his 2009 article in the Journal of the Copyright Society of the USA, concluded that the identity of the original lyricist is, by every available investigative method, unknowable. The lyrics emerged in the substantially uncoordinated folk-evolution manner characteristic of educational and children’s material in the early 20th century — circulating, modifying, recombining, and accumulating into something approximately consistent through the cumulative actions of unrecorded teachers, choral directors, parents, and songbook compilers, none of whom appears to have considered the substitution worth documenting or claiming credit for. By 1924, when the editor Robert H. Coleman included an unauthorised version of the song with the birthday lyrics in a popular songbook he was compiling, the new lyrics were already in sufficiently widespread folk use that Coleman’s contribution was substantially that of a passive transcriber rather than an original author. By the early 1930s, the song had been adopted by the Broadway musical The Band Wagon (1931), by Western Union’s first singing telegram service (1933), and by Irving Berlin’s musical As Thousands Cheer (1933) — without any of these productions paying royalties to the Hill estate or attributing the underlying melody to its actual composers.

The copyright that should never have existed

The third Hill sister, Jessica Mateer Hill, who survived both of her musically more famous siblings, filed a copyright infringement lawsuit in 1934 against the unauthorised commercial uses of the song. As described in the Berkeley Technology Law Journal’s reconstruction of the legal history of the Happy Birthday copyright, Jessica successfully demonstrated in court that “Happy Birthday to You” was derived from “Good Morning to All” and that the Hill family therefore retained legal interest in any commercial use of the underlying melody. The Clayton F. Summy Company subsequently registered a copyright for “Happy Birthday to You” in 1935 — crediting two specific individuals named Preston Ware Orem and Mrs. R. R. Forman as the authors of the lyrics, which neither of them had written, in what was substantially a paperwork formality to clean up the copyright claim that Jessica’s lawsuit had established. The copyright was sold, repeatedly, across the subsequent six decades — eventually purchased in 1988 by Warner Chappell Music as part of a $25 million acquisition. By the early 21st century, the song was generating approximately $2 million per year in royalties — an estimated total of more than $50 million across the 27 years of Warner Chappell’s ownership.

The copyright was successfully challenged in federal court in 2015. As reported in the US Copyright Office’s own historical summary of the dispute over the song’s intellectual property status, a documentary filmmaker named Jennifer Nelson filed a class-action lawsuit in 2013 against Warner Chappell, arguing that the 1935 copyright registration covered only a specific piano arrangement of the song rather than the underlying melody and lyrics themselves — and that, since the actual author of the “Happy Birthday” lyrics was unknown and the lyrics had been circulating in the public domain for more than two decades before any copyright registration had been filed, the song’s lyrics could not be validly copyrighted. The federal court agreed in September 2015. A settlement was approved in 2016 that returned approximately $14 million in collected royalties and placed “Happy Birthday to You” formally in the public domain. The original 1893 composition by the Hill sisters has, by the EU copyright clock, been in the public domain in the European Union since 1 January 2017, the year following the 70th anniversary of Patty Hill’s death. The unknown person who, sometime around 1910 or 1911, first substituted “Happy birthday to you” for “Good morning to you” and produced what would become the most frequently sung piece of music in human history — has never been identified, never collected a royalty payment, and remains, in the documentary record of late-19th- and early-20th-century American music, one of the more consequential anonymous individuals in modern cultural history.