Towcester is the oldest town in Northamptonshire.  Its origins can be traced back to the middle stone age and thus it can be said to be as old as any community in Britain. 

Towcester Orginates from the Old English Tófe-ceaster. Tófe refers to the River Tove; Bosworth and Toller compare it to the "Scandinavian proper names" Tófi and Tófa. The Old English ceaster comes from the Latin castra("camp") and was "often applied to places in Britain which had been originally Roman encampments." Thus, Towcester means "Camp on the (river) Tove."

Prehistoric and Roman periods

Lactodurum
Towcester lays claim to being one of the oldest towns in Northamptonshire and because of the antiquity of recent Iron Age finds in the town, to be one of the oldest inhabited settlements in the country. There is evidence that it was settled in since the Mesolithic era (middle stone age). There is also evidence of Iron Age burials in the area.

In Roman Britain, Watling Street (now the A5 road), was built through the area and a garrison town called Lactodurum established on the site of the present-day town. Two candidate sites for the Battle of Watling Street, fought in 61AD, are located close to the town, these are Church Stowe which is located 7 km to the north and Paulerspury which is 5 km to the south.

Lactodurum was surrounded by a wall that was strengthened at several points by brick towers. Substantial remains of one of these towers could be seen until the 1960s, when it was demolished to make way for a telephone exchange. The wall was also surrounded by a ditch part of which became the Mill Leat on the east side of the town.

The modern day St Lawrence's Church in Towcester may have occupied the site of a large Roman civic building, possibly a temple. Small fragments of Roman pavement can be seen next to the church's boiler room.

It is also thought that a Roman pillar is in the garden of one of the houses along Watling Street.

When the Romans left in the 5th century, the area was settled by Saxons. In the 8th century, the Watling Street became the frontier between the kingdom of Wessex and Danelaw, and thus Towcester became a frontier town.

Edward the Elder fortified Towcester in 914. In the 11th century, the Normans built a motte and bailey castle on the site. Bury Mount are the remains of the fortification and is a scheduled Ancient Monument. It was renovated in 2008 with an access ramp added and explanatory plaques added.