Walter Capellanus was a prominent Roman Catholic bishop and political figure in the Kingdom of Scotland during the reigns of William the Lion and Alexander II.
Notable developments during his tenure include the extension of the nave and the construction of the south-west door and the entrance to the Blacader Aisle.
[2] In 1218, he traveled to Rome with the bishops of Moray and Caithness to obtain absolution for the excommunication imposed on King Alexander II and the Kingdom of Scotland by the papal legate, Guala Bicchieri.
On 19 May 1232, he granted a charter to Kelso Abbey, a prominent Tironensian monastery, which reflected his broader involvement in the Scottish religious community.
He left a lasting legacy through his contributions to the construction of Glasgow Cathedral and his diplomatic efforts on behalf of the Scottish church.