In Irish it was Achadh Úr, meaning a fresh green field, but as the name passed through anglicisation the word for field was quietly replaced by ford, and the original meaning was lost. That quirk of translation turns out to be only the first of several oddities. Looked at closely, the street plan of Freshford preserves the ghost of a medieval monastic enclosure within it, two concentric curving boundaries visible in the south-east quadrant of the town that once defined the edge of church land. On the first Ordnance Survey map of 1839 the ground between these curves is marked as Glebe. More intriguingly still, a pair of earthworks on the north bank of the Nuenna River curves southward in a way that suggests the river was not simply a boundary for the early monastery but was actually folded inside it, part of the enclosure rather than its limit.

The monastery itself was founded by St Lachtain, who died in 622, sometime in the late sixth or early seventh century. The Annals record its turbulent early medieval history with some precision: in 836 the churches of St Lachtain were burned by the foreigners, the standard annalistic term for Viking raiders, and in 1018 the Abbot of Achadh Úr, Ua Brodubhain, was killed. By 1218 Freshford had likely served as an Episcopal See and was drawn into the temporalities of the See of Ossory. In 1245 Henry III granted Geoffry de Turville, Bishop of Ossory, a yearly fair to be held at his manor of Athethur from the 8th to the 15th of July. A decade later, in the 1250s, Bishop Hugh Mapleton built an Episcopal Palace at Aghore, later known as Uppercourt, complete with fish-ponds and the other expected features of a manorial residence. The town remained an ecclesiastical manor for several more centuries until 1570, when Bishop Christopher Gaffney of Ossory transferred it to Richard Shee of Kilkenny. It stayed in the Shee family until 1653, when Richard's grandson, also named Richard, forfeited it under Cromwell and the property passed to Sir George Askew. The large market square that dominates the south-west quarter of the town, roughly 130 metres by 80 metres, was probably laid out in the late seventeenth or eighteenth century, part of a broader commercialisation of the Kilkenny agricultural economy; Freshford received a boost to its markets and fairs in 1675. At the north side of that square the base of a stone cross survives, and near the town's central crossroads the parish church retains a Romanesque porch, a rounded-arch doorway of the kind associated with twelfth-century Irish ecclesiastical architecture, its presence quietly anchoring more than a thousand years of continuous use on the same ground.