The name is a bit of a misnomer, as the building was constructed as a chancel by the Grey Friars of Chichester, an Order of Franciscans.

The Grey Friars received the land, now called Priory Park, in a grant from Richard, Earl of Cornwall, in 1269.

[2] The first record of The Guildhall in Priory Park talks of an ordination held by Archbishop John Peckham, in 1283.

This modification to the building was executed so as to allow the chancel arch to remain visible spanning the whole width of the structure.

Symmetrical windows separated by buttresses line the northern and southern sides of the building.