who wrote it?
The anonymous poet is referred to by scholars as the ""Beowulf" poet".
Beowulf
The anonymous poet is referred to by scholars as the ""Beowulf" poet".

when is beowulf believed to have been written between 975 and 1025
wiki:1600659
Beowulf [SEP] Introduction
After Beowulf slays him, Grendel's mother attacks the hall and is then also defeated. Victorious, Beowulf goes home to Geatland (Götaland in modern Sweden) and becomes king of the Geats. Fifty years later, Beowulf defeats a dragon, but is mortally wounded in the battle. After his death, his attendants cremate his body and erect a tower on a headland in his memory. The poem survives in a single copy in the manuscript known as the Nowell Codex. It has no title in the original manuscript, but has become known by the name of the story's protagonist. In 1731, the manuscript was damaged by a fire that swept through Ashburnham House in London that had a collection of medieval manuscripts assembled by Sir Robert Bruce Cotton; the margins were charred, and a number of readings were lost.