Bulfinch's Mythology: The Age of Chivalry

Brutus built his capital city, and called it Trojanova (New Troy),
changed in time to Trinovantum, now London;* and, having governed
the isle twenty-four years, died, leaving three sons, Locrine,
Albanact, and Camber. Locrine had the middle part, Camber the west,
called Cambria from him, and Albanact Albania, now Scotland. Locrine
was married to Guendolen, the daughter of Corineus; but, having seen a
fair maid named Estrildis, who had been brought captive from
Germany, he became enamored of her, and had by her a daughter, whose
name was Sabra. This matter was kept secret while Corineus lived;
but after his death, Locrine divorced Guendolen, and made Estrildis
his queen. Guendolen, all in rage, departed to Cornwall, where
Madan, her son, lived, who had been brought up by Corineus, his
grandfather. Gathering an army of her father's friends and subjects,
she gave battle to her husband's forces, and Locrine was slain.
Guendolen caused her rival, Estrildis, with her daughter Sabra, to
be thrown into the river, from which cause the river thenceforth
bore the maiden's name, which by length of time is now changed into
Sabrina or Severn. Milton alludes to this in his address to the river-
and in

"Severn swift, guilty of maiden's death";-