Which Flemish poet wrote a 1561 April Fools' poem about foolish errands?

Flemish poet Eduard de Dene wrote the 1561 April Fools’ poem about foolish errands.

The poem describes a nobleman sending his servant on foolish errands on April 1. It is an unusually clear early account of the prank tradition: rather than merely naming an April custom, it depicts the social mechanism of assigning someone an absurd task for amusement.

Eduard de Dene was a sixteenth-century poet from the Low Countries, and his work provides an important piece of evidence in discussions about April Fools’ Day. The poem predates France’s 1564 adoption of January 1 as the official start of the year, which complicates the popular explanation that April Fools’ customs began solely because people resisted that calendar change.

The date is sometimes reported differently in summaries because the poem’s publication and manuscript history are treated separately. Nevertheless, the commonly cited 1561 reference is associated with de Dene and is earlier than the formal calendar reform often invoked in origin stories.