Defending Chichester against attacks over the centuries

For at least 200 years, the city limits of Roman Chichester were defined by nothing more than a small bank and ditch. Towards the end of the 3rd Century, the town was surrounded by a solid masonry wall that was approximately 4.1m (13.5ft) high. The city walls were built around 200 years after the Romans arrived and were a statement of civic pride as well as being important for defence. Four main gates in the walls controlled trade and 12m-tall bastions were added to the walls in the 4th Century due to the increase in threats noticeable throughout the Roman Empire.

After the Romans left Chichester, the town was largely deserted for 500 years. During Saxon times, Burhs (forts) were established as a defence against the Danes and the city walls, which had fallen into a state of disrepair, were then repaired.

Following the Norman Conquest in 1066, Roger de Montgomery ordered the construction of a castle in Chichester. It was placed in the north-east corner of the city protected by the city walls (modern day Priory Park). The castle was of timber construction and a motte and bailey design. Motte and bailey castles comprised a large conical mound of earth or rubble surmounted by a stone or timber tower, the motte, with an accompanying courtyard surrounded by a palisade, the bailey.

In 1216, the castle, along with many others in southern England, was captured by the French. This was part of the First Barons' War against King John of England. Spring 1217 saw the castle recaptured by the English. Due to its vulnerability that same year, Henry III ordered the castle's destruction.

During the English Civil War (1642 – 1649), Chichester was declared by local MP William Cawley as a supporter of Parliament. Control of the city was later taken by those loyal to the King. After fleeing the city, Cawley wrote a letter explaining the situation, which resulted in Parliamentary forces being sent to recapture Chichester. Parliamentary forces arrived outside the walls on December 21, 1642, and besieged the city, mounting cannon on the roof of St Pancras Church. The Royalists surrendered on December 27; however troops were garrisoned in Chichester for four years.

To slow the spread of the disease during the 1655 plague outbreak, the city gates were closed and residents were instructed to stay within the city walls until the plague was over. The people of Bosham prevented an even higher mortality rate by taking food to citizens of Chichester and leaving it outside the gates.

The 18th century saw the introduction of a camp on The Broyle, as Britain responded to threats highlighted by the French Revolution. The camp, which started as tented accommodation, developed overtime and by 1803, wooden structures were erected on the site.

During the Napoleonic War, French prisoners-of-war were detained at the camp and, in 1814, these prisoners were responsible for the initial building of the flint and brick boundary wall, which still remains on the north and east sides of the site. In 1873, it became the garrison home for the Royal Sussex Regiment.

In 1939, following the declaration of war, defence precautions were quickly put into place with the formation of Air Raid Precaution (ARP) wardens, the Auxiliary Fire Service and Home Guard. The City Council set up local Civil Defence headquarters in North Street. This was also where the ARP headquarters were. The Home Guard was formed following a radio appeal by Minister of War, Anthony Eden, for volunteers to join the new units.

Air-raid siren trials had already begun in April 1939 and ARP wardens took part in large scale rehearsals and training to prepare for war. This included exercises at the Assembly Rooms in North Street, which involved rescuing casualties from buildings, dealing with a crashed aircraft and responding to fire.

The threat of bombing raids was present in the city. An assessment highlighted existing facilities would not cope with the threat of fire spreading through the city. Precautions were taken, including the placement of sandbags outside council offices, air raid shelter construction in Priory Park and large metal static water tanks being erected. These provided water for extinguishing fires in the event the mains were damaged, including one to the south-west of the Guildhall in Priory Park.

In Brandy Hole Copse, evidence remains of anti-tank blocks built at this time. The mature trees and earthworks in this area also hid 25 Canadian Churchill tanks in 1942.

Still visible today are other elements of the defensive perimeter built around Chichester. In 2019, during the building of a new supermarket, developers found more than 100 anti-tank blocks, which would have been positioned in a continuous line along the top of the beach to stop enemy tanks in the event of an invasion. At the end of the war many of these blocks were removed and buried in disused gravel pits around Chichester.