All that remains of our long history as a parish is the ruined Church of St Fintan on St Fintan’s Park, and the house called Kill Abbey, which, though it has lost its original characteristics, is surrounded by yew trees of a great age.  These building stood in the centre of a property owned by the Augustinian Canons of the Priory of the Holy Trinity (the builders of Christ Church Cathedral) It was to Kill of the Grange that the Augustinians came for the country air and to carry on the business of their farm estates, which once occupied most of our present parish of the Holy Family. A small village known as the ‘town of the Grange’ compromising of thirty-five houses was the Kill of the Grange of old.  This village housed the employees of the monastery – a bailiff, two smiths, a weaver, and a chamberlain.  The tenants of the Priory in the 14th century were prosperous and well to do.  The peculiar properties of the soil close to the village led in times to the sale of clay from making earthenware vessels, which became a source of revenue to the Priory. The name Pottery Road probably finds its origins in this detail.

The Prior, like a landowner, exercised jurisdiction over the tenants and a court was regularly held at Kill of the Grange, to redress misdemeanours and nuisances and to settle disputes over property.  The ancient rolls of the Priory record that the thinning and weeding of crops required 66 labourers and during the harvest 88 men were employed on any one day.  This army of workers were fed by the canons of the Priory on pork and herrings, bread and ale.  With the dissolution of the monasteries under Henry VIII, in 1539, the Priory was reconstructed as the Cathedral establishment of the church of the Holy Trinity, now Christ Church.

The Church on St Fintan’s Park may date from the 10th century.  Unfortunately, this ruin is now closed to the public having suffered from vandalism and the breaking of headstones.

The present Parish of Kill O’ the Grange was created in 1972 from the existing parishes of Monkstown and Dun Laoghaire. The first Parish Priest was Fr Andrew Griffith.  The parish has about 3,000 housing units.  The Parish National School of Holy Family is situated in Dunedin Avenue