Device Forts
The Device Forts, also known as Henrician castles and blockhouses, were a series of artillery fortifications built to defend the coast of England and Wales by Henry VIII. Traditionally, the Crown had left coastal defences in the hands of local lords and communities but the threat of French and Spanish invasion led the King to issue an order, called a "device", for a major programme of work between 1539 and 1547. The fortifications ranged from large stone castles positioned to protect the Downs anchorage in Kent, to small blockhouses overlooking the entrance to Milford Haven in Pembrokeshire, and earthwork bulwarks along the Essex coast. Some forts operated independently, others were designed to be mutually reinforcing. The Device programme was hugely expensive, costing a total of £376,000 ; much of this was raised from the proceeds of the Dissolution of the Monasteries a few years before.
These utilitarian fortifications were armed with artillery, intended to be used against enemy ships before they could land forces or attack ships lying in harbour. The first wave of work between 1539 and 1543 was characterised by the use of circular bastions and multi-tiered defences, combined with many traditional medieval features. These designs contained serious military flaws, however, and the second period of construction until 1547 saw the introduction of angular bastions and other innovations probably inspired by contemporary thinking in mainland Europe. The castles were commanded by captains appointed by the Crown, overseeing small garrisons of professional gunners and soldiers, who would be supplemented by the local militia in an emergency.
Despite a French raid against the Isle of Wight in 1545, the Device Forts saw almost no action before peace was declared in 1546. Some of the defences were left to deteriorate and were decommissioned only a few years after their construction. After war broke out with Spain in 1569, Elizabeth I improved many of the remaining fortifications, including during the attack of the Spanish Armada of 1588. By the end of the century, the defences were badly out of date and for the first few decades of the 17th century many of the forts were left to decay. Most of the fortifications saw service in the First and Second English Civil Wars during the 1640s and were garrisoned during the Interregnum, continuing to form the backbone of England's coastal defences against the Dutch after Charles II was restored to the throne in 1660. Again left to fall in ruin during the 18th century, many of the Device Forts were modernised and rearmed during the Napoleonic Wars, until peace was declared in 1815.
Fears over a possible French invasion resurfaced several times in the 19th century, combined with rapid changes in technology, such as the development of steamships and shell guns in the 1840s, rifled cannon and iron-clad warships in the 1850s, and torpedo boats in the 1880s. This spurred fresh investment in those Device Forts still thought to be militarily valuable, and encouraged the decommissioning of others. By 1900, however, developments in guns and armour had made most of the Device Forts that remained in service simply too small to be practical in modern coastal defence. Despite being brought back into use during the First and Second World Wars, by the 1950s the fortifications were finally considered redundant and decommissioned for good. Coastal erosion over the centuries had taken its toll and some sites had been extensively damaged or completely destroyed. Many were restored, however, and opened to the public as tourist attractions.
Early history and design
Device programme
Background
The Device Forts emerged as a result of changes in English military architecture and foreign policy in the early 16th century. During the late medieval period, the English use of castles as military fortifications had declined in importance. The introduction of gunpowder in warfare had initially favoured the defender, but soon traditional stone walls could easily be destroyed by early artillery. The few new castles that were built during this time still incorporated the older features of gatehouses and crenellated walls, but intended them more as martial symbols than as practical military defences. Many older castles were simply abandoned or left to fall in disrepair.Although fortifications could still be valuable in times of war, they had played only a limited role during the Wars of the Roses and, when Henry VII invaded and seized the throne in 1485, he had not needed to besiege any castles or towns during the campaign. Henry rapidly consolidated his rule at home and had few reasons to fear an external invasion from the continent; he invested little in coastal defences over the course of his reign. Modest fortifications existed along the coasts, based around simple blockhouses and towers, primarily in the south-west and along the Sussex coast, with a few more impressive works in the north of England, but they were very limited in scale.
His son, Henry VIII inherited the throne in 1509 and took a more interventionist approach in European affairs, fighting one war with France between 1512 and 1514, and then another between 1522 and 1525, this time allying himself with Spain and the Holy Roman Empire. While France and the Empire were in conflict with one another, raids along the English coast might still be common, but a full-scale invasion seemed unlikely. Indeed, traditionally the Crown had left coastal defences to local lords and communities, only taking a modest role in building and maintaining fortifications. Initially, therefore, Henry took little interest in his coastal defences; he declared reviews of the fortifications in both 1513 and 1533, but not much investment took place as a result.
In 1533 Henry broke with Pope Clement VII in order to annul the long-standing marriage to his wife, Catherine of Aragon, and remarry. Catherine was the aunt of King Charles V of Spain, who took the annulment as a personal insult. As a consequence, France and the Empire declared an alliance against Henry in 1538, and the Pope encouraged the two countries to attack England. An invasion of England now appeared certain; that summer Henry made a personal inspection of some of his coastal defences, which had recently been mapped and surveyed: he appeared determined to make substantial, urgent improvements.
Initial phase, 1539–1543
Henry VIII gave instructions through Parliament in 1539 that new defences were to be built along the coasts of England, beginning a major programme of work that would continue until 1547. The order was known as a "device", which meant a documented plan, instruction or schema, leading to the fortifications later becoming known as the "Device Forts". The initial instructions for the "defence of the realm in time of invasion" concerned building forts along the southern coastline of England, as well as making improvements to the defences of the towns of Calais and Guisnes in France, then controlled by Henry's forces. Commissioners were also to be sent out across south-west and south-east England to inspect the current defences and to propose sites for new ones.The initial result was the construction of 30 new fortifications of various sizes during 1539. The stone castles of Deal, Sandown and Walmer were constructed to protect the Downs in east Kent, an anchorage which gave access to Deal Beach and on which an invasion force of enemy soldiers could easily be landed. These defences, known as the castles of the Downs, were supported by a line of four earthwork forts, known as the Great Turf Bulwark, the Little Turf Bulwark, the Great White Bulwark of Clay and the Walmer Bulwark, and a long defensive ditch and bank. The route inland through a gap in the Kentish cliffs was guarded by Sandgate Castle. In many cases temporary bulwarks for artillery batteries were built in during the initial stages of the work, ahead of the main stonework being completed.
The Thames estuary leading out of London, through which 80 percent of England's exports passed, was protected with a mutually reinforcing network of blockhouses at Gravesend, Milton, and Higham on the south side of the river, and West Tilbury and East Tilbury on the opposite bank. Camber Castle was built to protect the anchorage outside the ports of Rye and Winchelsea, defences were built in the port of Harwich and three earth bulwarks were built around Dover. Work was also begun on Calshot Castle in Fawley and the blockhouses of East and West Cowes on the Isle of Wight to protect the Solent, which led into the trading port of Southampton. The Portland Roads anchorage in Dorset was protected with new castles at Portland and Sandsfoot, and work began on two blockhouses to protect the Milford Haven Waterway in Pembrokeshire.
In 1540 additional work was ordered to defend Cornwall. Carrick Roads was an important anchorage at the mouth of the River Fal and the original plans involved constructing five new fortifications to protect it, although only two castles, Pendennis and St Mawes, were actually built, on opposite sides of the estuary. Work began on further fortifications to protect the Solent in 1541, with the construction of Hurst Castle, overlooking the Needles Passage, and Netley Castle just outside Southampton itself. Following a royal visit to the north of England, the coastal fortifications around the town of Hull were upgraded in 1542 with a castle and two large blockhouses. Further work was carried out in Essex in 1543, with a total of seven fortifications constructed, three in Harwich itself, three protecting the estuary leading to the town, and two protecting the estuary linking into Colchester. St Andrew's Castle was begun to further protect the Solent.
The work was undertaken rapidly, and 24 sites were completed and garrisoned by the end of 1540, with almost all of the rest finished by the end of 1543. By the time they were completed, however, the alliance between Charles and Francis had collapsed and the threat of imminent invasion was over.