A few lines of music written down 1,100 years ago, spotted by chance by a postgraduate student in a manuscript in the British Library, have proved to be the earliest example of polyphonic choral music, where the voices sing different melodies combining to make one composition.

The scrap of music, which would have lasted no more than a few seconds, was written on the bottom of a page of a portrait of a saint and has been dated to around AD900. Although there are very early treatises on such music, the discovery is the earliest practical example intended for use by singers – the next oldest known is from a collection known as the Winchester Troper, originally made for Winchester cathedral and dated to around 1000.

The short composition in praise of Saint Boniface was spotted by chance by Giovanni Varelli, a PhD student from St John’s College, Cambridge, while he was an intern at the British Library. Varelli, who specialises in early music notation, spotted that the piece was written for two voices. He believes its significance was missed by other scholars because the notation, which pre-dates the invention of the stave, is hard to read for non-specialists.

Quintin Beer (left) and John Clapham (right), both music undergraduates at St John’s College, University of Cambridge. The film was shot by Ryan Cronin.

He said the unknown composer was already experimenting with the style, breaking the rules as they then stood. “What’s interesting here is that we are looking at the birth of polyphonic music and we are not seeing what we expected. Typically, polyphonic music is seen as having developed from a set of fixed rules and almost mechanical practice. This changes how we understand that development precisely because whoever wrote it was breaking those rules. It shows that music at this time was in a state of flux and development. The conventions were less rules to be followed than a starting point from which one might explore new compositional paths.”

Although the composer and the origin of the manuscript are unknown, Varelli,who has put extensive detective work into his discovery, believes the style of notation, known as Eastern Palaeofrankish, suggests it came from a monastery in the region of Düsseldorf or Paderborn in modern north-west Germany.

The piece was written on the blank space at the bottom of a page of the life of Bishop Maternianus of Reims. Another scribe has added a Latin inscription at the top of the page that translates as “which is celebrated on December 1”. Varelli said the date helped narrow his search for the origin of the manuscript, because although most monastic houses celebrated the saint’s day on April 30, a handful in Germany marked it on December 1 instead.

The style would be refined and developed for many centuries, becoming far more elaborate than a simple chant for two monks.

“The rules being applied here laid the foundations for those that developed and governed the majority of western music history for the next thousand years. This discovery shows how they were evolving, and how they existed in a constant state of transformation, around the year 900.”