Wealthow is King Hrothgar's wife and the Lady of the Danes. She is characterized by nobility and the qualities which would have been idolized in a woman of great stature. She maintains a sense of dignity, commands an air of respect, and is also very intelligent. Her biggest role in the play is to present Beowulf with a gift (a necklace) that is symbolically meant to secure friendship between her kingdom and his. She knows how to use her femininity to her advantage, but does not overstep her boundaries as a woman nor a wife. She is motivated by her status as the King's wife and by her duty to maintain social harmony between warring kingdoms, as was customary of queens at that time.
After Beowulf kills Grendel, the feast in the Great Hall is the first time we see Wealthow display these qualities and show where her heart lies. First, she praises Beowulf profusely, appealing to his ego. She then bestows gifts upon him. And just when he is at the point of drinking from a cup of "friendship" offered him, by her, she secures the future of her own sons by asking for Beowulf's protection. This shows that she is politically savvy, and also suspects a man like Beowulf might one day attempt to take the throne for himself.
I know your nephew's kindness, I know
He'll repay in kind the goodness you have shown him,
Support your two young sons as you
And I sustained him in his own early days... (1183-1186)