The largest recorded explosion in 17th-century England, the Great Blow killed up to 200 people and destroyed 40 buildings during a pro-royalist riot.
Key Facts
- Gunpowder barrels detonated
- 98 barrels accidentally exploded in Committee House
- Estimated deaths
- 80 to 200 people
- Buildings destroyed
- 40 buildings
- Estimated damage
- £20,000 (≈£2,840,425 in 2023)
- Men executed after trial
- 8 of 108 tried were executed
- Date of riot petition
- 18 April 1648
By the Numbers
Location
Cause → Event → Consequence
Tensions in Norwich stemmed from grievances over excise taxes, restrictive church policies, and impressment. A petition on 18 April 1648 accused Mayor John Utting of installing royalists in local positions and demanded his arrest. Utting's counter-petition galvanised royalist sympathisers, setting off a riot during the Second English Civil War.
On 24 April 1648, a pro-royalist riot spread from the city market and Chapel Field to the homes of the mayor's supporters. Rioters reached the gunpowder stores held in Committee House, where 98 barrels of gunpowder were accidentally detonated in what became the largest explosion recorded in England in the 17th century.
The blast killed an estimated 80 to 200 people, shattered windows in two nearby churches, and destroyed 40 buildings causing roughly £20,000 in damage. Of 108 men tried, eight were executed, 26 fined, seven imprisoned, and two whipped. The event was variously labelled a 'mutiny', 'blow', or 'crack' by contemporaries.
Political Outcome
The royalist riot was suppressed; eight rioters were executed and others fined or imprisoned, reaffirming Parliamentary authority in Norwich.
Royalist influence gaining ground in Norwich local governance under Mayor John Utting
Parliamentary forces reasserted control following trials and punishments of riot participants