Describe Beowulf's upbringing

We learn that Beowulf was actually a foster child.

"At seven, I was fostered out by my father,
left in the charge of my people's lord.
King Hrethel kept me and took care of me,
was open-handed, behaved like a kinsman.
While I was his ward, he treated me no worse
as a wean about the place than one of his own boys."