The Geats were Beowulf's clan - a seafaring tribe residing in the
south of Sweden. As the poem suggests, the Geats appear to have been
conquered and disappeared into history. The seafaring Geats appear to
be the invading `Danes' of whom Gregory of Tours writes concerning an attack
by Chlochilaicus (Hygelac) against the Franks in 520. Later
they were connected to the Gautar people who were eventually
subjugated by the Swedes in territory inland of Sweden.
Given this history, F.R. Klaeber speculates that Beowulf himself was born in about the year 495. He defeats Grendel and his mother to save Hroðgar's kingdom in 515. Following Hygelac's raid in 520, he eventually becomes king of the Geats when Heardred was killed in 533. Fifty years after that, the poem says that Beowulf is killed by the dragon, but few scholars are willing to commit to any specific date.
The Geats are referred to as the Geatas, Guð-Geatas (War-), the Sæ-Geatas (Sea-), and the Weder-Geatas (Weather-).