The medieval parish church of St Eilian's, Llaneilian,was originally a celtic 'clas' church. It consists of a late fifteenth century nave and chancel, an early sixteenth century south porch, a twelfth century west tower and a formerly detached late fourteenth century chapel - St Eilian's chapel (NPRN 43586).
The church famously retains many of its late medieval fittings and post-medieval restorations have been limited or restrained.
There are remains of a churchyard cross (NPRN 302479). The tower is a three stage roughcast structure rising to a high pyramidal roof or low spire. The stages are marked by offsets and the lower stage was formerly slate hung. It retains some Romanesque detail although the head of the eastern archway into the nave was renewed in the thirteenth-fourteenth century.
The nave and chancel are dated by consecration crosses of 1480 and 1481 on the nave butresses. This part of the church has a splendour which exceeds its size. Tudur Aled the poet attributed this to the rector Nicholas ab Ellis, archdeacon of Anglesey in 1474. The nave is a two bay structure with butresses between the bays and at the angles. The western bay has offset north and south doorways and the eastern bay is lit by three light windows. The chancel has corner butresses, a two light north window and a three light east window. Both nave and chancel have battlemented parapets with pinacles rising above the butresses.
The chancel arch is filled by a rare survival of a fifteenth century screen, above which the rood loft curves out into the nave. This is reached by a spiral stair springing from the south-west angle of the nave and rising to a low turret. The chancel retains its graven choir stalls. The roofs feature angels and other figures. There are traces of post medieval wall paintings. The famous painting of a skeleton, the 'image of death', is accompanied by the inscription 'Colyn Angau yw Pechod' or 'The sting of death is sin'.
Source: RCAHM Anglesey Inventory (1937), 59-61
John Wiles 05.09.07