After the death of Gilbert de Greenlaw, Bishop of Aberdeen, in 1421, Lichton was chosen as his successor, and was translated to the diocese of Aberdeen in early April 1422, on the authority of Pope Martin V. Pope Martin delegated authority to Robert de Cardeny, Bishop of Dunkeld, and William Stephen, Bishop of Dunblane, in order to take Lichton's oath to the Papal see without forcing him to travel to Rome.
It is of note that Lichton had already been in possession of the prebend of Kinkell in the Aberdeen diocese, a former possession of the Knights Hospitaller but attached to Aberdeen Cathedral by Lichton's time.

As Bishop of Aberdeen, Lichton was one of its greatest builders.
The Aberdeen Registrum noted that he began to rebuild the cathedral, and Hector Boece gave a description of his rebuilding, noting that although he finished the walls and two belltowers, the third belltower remained unfinished at his death.
Licthon also constructed a new chapel dedicated to St John the Evangelist, and donated much of his own money to new service books and vestments, as well as to the reconstruction of the cathedral.
He also authored several legal and religious texts, though none have survived.
After the death of Gilbert de Greenlaw, Bishop of Aberdeen, in 1421, Lichton was chosen as his successor, and was translated to the diocese of Aberdeen in early April 1422, on the authority of Pope Martin V. Pope Martin delegated authority to Robert de Cardeny, Bishop of Dunkeld, and William Stephen, Bishop of Dunblane, in order to take Lichton's oath to the Papal see without forcing him to travel to Rome. It is of note that Lichton had already been in possession of the prebend of Kinkell in the Aberdeen diocese, a former possession of the Knights Hospitaller but attached to Aberdeen Cathedral by Lichton's time.
As Bishop of Aberdeen, Lichton was one of its greatest builders. The Aberdeen Registrum noted that he began to rebuild the cathedral, and Hector Boece gave a description of his rebuilding, noting that although he finished the walls and two belltowers, the third belltower remained unfinished at his death. Licthon also constructed a new chapel dedicated to St John the Evangelist, and donated much of his own money to new service books and vestments, as well as to the reconstruction of the cathedral. He also authored several legal and religious texts, though none have survived.
Henry de Lichton