The historical character is Odo of Bayeux.

No idea where the "Borleng" bit comes from (Bayeux in old norse ?).

The time frame and "captured" trait do match since Odo the Bayeux was tried and imprisioned for a few years for some kind of conspiracy against the king (but do check if you can spare the time...).

Finally, IIRC correctly he pops up a bit before 1100. As far as I recall, if you produce ten units of holibars in a row as from 1087, he shows up among the last ones (just after Tancred of Normandy).