The town’s name originates from dic, an Anglo-Saxon word meaning ditch or embankment. Diss has several historic buildings, including an early 14th-century parish church and an 1850s Corn Hall, which is still in use. Under Edward the Confessor, Diss was part of the Hartismere hundred of Suffolk, It was recorded as such in the 1086 Domesday book. It is recorded as being in the king’s possession as demesne (direct ownership) of the Crown, there being at that time a church and a glebe of 24 acres (9.7 ha).

This was thought to be worth £15 per annum, which had doubled by the time of William the Conqueror to £30, with the benefit of the whole hundred and half belonging to it. It was then found to be a league long, around 3 miles (5 km) and half that distance wide, and paid 4d. in Danegeld. From this it appears that it was still relatively small, but it soon grew, when it subsumed Watlingsete Manor, a neighbouring area as large as Diss, and seemingly more populated according to the geld or tax that it paid. The town includes part of Heywode, as appears from its joining to Burston, into which the manor extended