About a 1000 years ago, the people of Portslade decided to build their own church. It was a little Norman church situated on a hill on the eastern side of the Old Village, overlooking the Channel. It became a landmark to sailors and was appropriately dedicated to St Nicolas, Patron Saint of Sailors.

Early records show that in the 12th c., St Nicolas Church was paying a tithe of 40s to the Priory of St Pancras at Lewes, the first Clunic House to be built in England. The petition below, from the Priory to St Peters, Rome requested that tithes should also be collected in the 1400's .

The Calendar of Papal Registers “Lateran Regista” records a letter received in St Peters, Rome on the 7th September 1401 from John Oke the Prior of St Pancras. "dated in the chapter-house of Lewes 26 Nov. 1400, which recapitaulate and confirm the grant by his predecessors as pittance to the sub-prior and convent of the following: all the fruits etc. of the churches-appropriate to the monastery by papal authority, portions for vicarages being alone excepted" the papal letter goes on to list the tithes required from 20 churches in the south of England, Portslade is named and was required to pay 20s. a year to the Priory.

The Church was built of rubble with stone dressing and the church now consists of a nave of three bays with north and south aisles, a chancel with modern north vestry, and western tower. At the west end of the north aisle is the Brakenbury Chapel which was built in 1869, and under the tower is the baptistery. There is also a south porch of uncertain date.

The oldest portion of the church is Norman, erected probably about the year 1150. The two southern pillars and the walls of the south aisle are of this period; the pillars were made of limestone imported from France. About 100 years later, the church was improved and enlarged. The old Norman apse was taken down and the present chancel (Early English) erected, but there still is a small portion of the Norman chancel arches left in the wall behind the pulpit. Thus the greater part of the building, including the tower, dates back to about 1250

The church is on ground, that slopes from west to east, and the chancel is not in line with the nave. By standing at the west end of the nave one notices that the chancel is inclined towards the south. It may have been the intentional that the chancel was built out of line so as to represent Our Lord's head leaning to one side when he was crucified, hence the term "Weeping Chancel". Situated in the south wall of the sanctuary is the sedilia and piscina, which are 13th century. The seats rise from west to east, below arch hood moulding which terminates at either end in mask-stops of crude design.

The seats in the sedilia were designed for the use of the Celebrant and his Assistants at Mass and the piscina is a stone dish with basin used for the ablutions at Mass, a ceremony when the Priest washes his hands, after the offertory (very necessary centuries ago when the faithful offered goods or poultry instead of money) and the used water is drained from the piscina to the ground. There are two fine lancet windows at the east end and good examples of 13th Century architecture. 

See http://www.stnicolas.standrewportslade.btinternet.co.uk/st_nicolas_church_history_portslade.htm for further information