Coordinates: 52°22′52″N 1°06′28″E / 52.3812°N 1.1079°E / 52.3812; 1.1079

Diss is a town (population 6,742) in Norfolk, England close to the border with the neighbouring East Anglian county of Suffolk.

The town lies in the valley of the River Waveney, around a mere (lake) that covers 6 acres (2.4 ha; 0.0094 sq mi). The mere is up to 18 feet (5.5 m) deep, although there is another 51 feet (16 m) of mud, making it one of the deepest natural inland lakes in England.^{[citation needed]} The town takes its name from dic an Anglo-Saxon word meaning either ditch or embankment.

Diss has a large number of historic buildings, including the early 14th century parish church. It is also home to a museum. Diss railway station lies on the Great Eastern Main Line route from London to Norwich.

In the time of Edward the Confessor, Diss was then officially included in Suffolk, in the Hartismere hundred (a hundred was an administrative subdivision), as recorded in the 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 twenty-four acres. This was considered to be worth £15 per annum, which had doubled by the time of William the Conqueror, it being then estimated at £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 (4.8 km) or nearly 5 kilometres), and half this distance broad, and paid 4d. (9.6 new pence) in Danegeld. From this it appears that it was still relatively small, but it grew shortly after when it subsumed Watlingsete Manor, a neighbouring area, which was as large as Diss, and seemingly fuller of inhabitants, according to the geld or tax that it paid. This was afterwards called Walcote, and includes part of Heywode, as appears from its joining to Burston, into which town this manor extended.