This is the world's oldest known song with complete music notation, it even has lyrics. It was found on clay tablets, recorded in cuneiform, in a lost city of Syria and dates back to around 1400 BC. It was discovered in the late 90s. The title of it translates to 'The Prayer of the Infertile Woman' and as a sad lament to the moon goddess of a childless (not "childfree" in this context!) wife asking why she could not bear children as others.
orchestral interpretation:
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simple version with lyrics, on a reproduction the lyre instrument of the time