Hurst Castle was built as a consequence of international tensions between England, France and the Holy Roman Empire in the final years of the reign of King Henry VIII.
Traditionally the Crown had left coastal defences to local lords and communities, only taking a modest role in building and maintaining fortifications, and while France and the Empire remained in conflict, maritime raids were common but an actual invasion of England seemed unlikely.
Modest defences based around simple blockhouses and towers existed in the south-west and along the Sussex coast, with a few more impressive works in the north of England, but in general the fortifications were limited in scale.
Worsley's Tower, for example, built opposite the future site of Hurst Castle in the 1520s, was too small to hold powerful artillery and considered by surveyors in 1539 to be "one of the worst devised things" they had seen.

In 1533, Henry broke with Pope Paul III over the annulment of his long-standing marriage to Catherine of Aragon.
Catherine was the aunt of Charles V, the Holy Roman Emperor, who took the annulment as a personal insult.
This resulted in France and the Empire declaring an alliance against Henry in 1538, and the Pope encouraging the two countries to attack England.
An invasion of England appeared certain.
In response, Henry issued an order, called a "device", in 1539, giving instructions for the "defence of the realm in time of invasion" and the construction of forts along the English coastline.

Hurst Castle was designed to protect the western entrance to the Solent, a body of water that led from the English Channel to the naval base at Portsmouth and, through Southampton Water, to the important port of Southampton.
The castle was one of four fortifications that William Fitzwilliam, the Lord Admiral, and William Paulet recommended building to strengthen the defences along the Solent; the others were at East and West Cowes, and Calshot.
It was positioned on the Hurst Spit, a strip of shingle sheltering saltmarsh and mud flats, only 0.75 miles (1.21 km) across the water from the Isle of Wight.
Temporary earthwork fortifications were erected on the site and, after the other three castles had been completed, work then began on Hurst in 1541 under the direction of John Mille, the financial controller, and probably Thomas Bertie, a master mason.
Bertie was appointed as the castle's captain in 1542 and the work was completed by January 1544, at a cost of over £3,200.

The result was a stone artillery fort with a central keep and three bastions, surrounded by a moat, capable of holding up to 71 guns.
In 1547, however, Hurst was equipped with 26 artillery pieces–four made of brass and the remainder iron–comprising a two sakers, a culverin, a demi-cannon, a curtall cannon, two demi-culverins, six portpieces, four slings, two quarter-slings, and seven bases, three of them inoperable.
A 1559 survey commented that Hurst Castle was essential for sending reinforcements from the mainland to the island, and noted that it was equipped with eleven brass and iron guns, with nine further broken guns, along with handguns, bows and arrows, pikes and bills.
The survey observed that the castle was vulnerable to attack because it lacked flanking protection and had rounded walls, and that it was expensive to garrison because of its size, requiring a captain, his deputy, twelve gunners, nine soldiers and a porter.
The historian John Kenyon notes, however, that its considerable armament made it one of the most powerful forts in the south, even if it was equipped with lighter guns than would have been ideal for its "ship-killing" role.

Meanwhile, the invasion threat from France had passed and a lasting peace was made in 1558; government concerns shifted away from the south coast towards the Spanish threat to the south-west of England.
By 1569, when Thomas Carew was serving as Hurst's captain, there were less than ten guns but the same size of garrison to that seven years before.
His son, Sir Thomas Gorges, became captain in turn, and in 1593 he reported that the castle
Hurst Castle was built as a consequence of international tensions between England, France and the Holy Roman Empire in the final years of the reign of King Henry VIII. Traditionally the Crown had left coastal defences to local lords and communities, only taking a modest role in building and maintaining fortifications, and while France and the Empire remained in conflict, maritime raids were common but an actual invasion of England seemed unlikely. Modest defences based around simple blockhouses and towers existed in the south-west and along the Sussex coast, with a few more impressive works in the north of England, but in general the fortifications were limited in scale. Worsley's Tower, for example, built opposite the future site of Hurst Castle in the 1520s, was too small to hold powerful artillery and considered by surveyors in 1539 to be "one of the worst devised things" they had seen.
In 1533, Henry broke with Pope Paul III over the annulment of his long-standing marriage to Catherine of Aragon. Catherine was the aunt of Charles V, the Holy Roman Emperor, who took the annulment as a personal insult. This resulted in France and the Empire declaring an alliance against Henry in 1538, and the Pope encouraging the two countries to attack England. An invasion of England appeared certain. In response, Henry issued an order, called a "device", in 1539, giving instructions for the "defence of the realm in time of invasion" and the construction of forts along the English coastline.
Hurst Castle was designed to protect the western entrance to the Solent, a body of water that led from the English Channel to the naval base at Portsmouth and, through Southampton Water, to the important port of Southampton. The castle was one of four fortifications that William Fitzwilliam, the Lord Admiral, and William Paulet recommended building to strengthen the defences along the Solent; the others were at East and West Cowes, and Calshot. It was positioned on the Hurst Spit, a strip of shingle sheltering saltmarsh and mud flats, only 0.75 miles (1.21 km) across the water from the Isle of Wight. Temporary earthwork fortifications were erected on the site and, after the other three castles had been completed, work then began on Hurst in 1541 under the direction of John Mille, the financial controller, and probably Thomas Bertie, a master mason. Bertie was appointed as the castle's captain in 1542 and the work was completed by January 1544, at a cost of over £3,200.
The result was a stone artillery fort with a central keep and three bastions, surrounded by a moat, capable of holding up to 71 guns. In 1547, however, Hurst was equipped with 26 artillery pieces–four made of brass and the remainder iron–comprising a two sakers, a culverin, a demi-cannon, a curtall cannon, two demi-culverins, six portpieces, four slings, two quarter-slings, and seven bases, three of them inoperable. A 1559 survey commented that Hurst Castle was essential for sending reinforcements from the mainland to the island, and noted that it was equipped with eleven brass and iron guns, with nine further broken guns, along with handguns, bows and arrows, pikes and bills. The survey observed that the castle was vulnerable to attack because it lacked flanking protection and had rounded walls, and that it was expensive to garrison because of its size, requiring a captain, his deputy, twelve gunners, nine soldiers and a porter. The historian John Kenyon notes, however, that its considerable armament made it one of the most powerful forts in the south, even if it was equipped with lighter guns than would have been ideal for its "ship-killing" role.
Meanwhile, the invasion threat from France had passed and a lasting peace was made in 1558; government concerns shifted away from the south coast towards the Spanish threat to the south-west of England. By 1569, when Thomas Carew was serving as Hurst's captain, there were less than ten guns but the same size of garrison to that seven years before. His son, Sir Thomas Gorges, became captain in turn, and in 1593 he reported that the castle
Hurst Castle