Roolwer's name appears to correspond to the Old Norse Hrólfr, which could mean that he is identical to either of two contemporary like-named bishops of Orkney.
The site of Roolwer's cathedral is unknown, although Maughold and St Patrick's Isle are possibilities.
[12] Another noted contemporary of Roolwer was Dúnán, an ecclesiast generally assumed to have been the first Bishop of Dublin.
[11] In fact, the surviving stone tower on this island appears to date to the mid eleventh century, and made have been erected by Roolwer himself.
Therefore, like Gilla Pátraic in Dublin, Roolwer's episcopacy in the Isles may well have begun in 1074 after Dúnán's death, and perhaps ended at some point during Gofraid Crobán's reign.