Seikilos epitaph
The Seikilos epitaph is the oldest surviving complete musical composition, including musical notation, from anywhere in the world. The epitaph has been variously dated, but seems to be either from the 1st or the 2nd century AD. The song, the melody of which is recorded, alongside its lyrics, in the ancient Greek musical notation, was found engraved on a tombstone (a stele) from the Hellenistic town Tralles near present-day Aydın, Turkey, not far from Ephesus. It is a Hellenistic Ionic song in either the Phrygian octave species or Iastian tonos. While older music with notation exists (for example the Hurrian songs), all of it is in fragments; the Seikilos epitaph is unique in that it is a complete, though short, composition.
Widsith
There is some controversy as to when "Widsith" was first composed. Some historians, such as John Niles, argue that the work was invented after King Alfred's rule to present "a common glorious past", while others such as Kemp Malone have argued that the piece is an authentic transcription of old heroic songs. Among the works appearing in the Exeter Book, there are none quite like "Widsith", which may be by far the oldest extant work that gives a historical account of the Battle of the Goths and the Huns, recounted as legends in later Scandinavian works such as the Hervarar saga. Archaeologist Lotte Hedeager argues that "Widsith" goes back to Migration Age history--at least part of it was composed in the 6th century, and that the author demonstrates familiarity with regions outside of Britain, including Denmark and the Baltic coast.