France in October 1231. HenryIII summoned troops to invade Guienne in 1242, and EdwardI sent supplies for his army in France in 1295. Commercial interests had grown by the following century, and its exports included wool, corn, grain, and livestock. Edward II ordered all ports on the south coast to assemble their largest vessels at Portsmouth to carry soldiers and horses to the Duchy of Aquitaine in 1324 to strengthen defences. A French fleet commanded by David II of Scotland attacked in the English Channel, ransacked the Isle of Wight and threatened the town. EdwardIII instructed all maritime towns to build vessels and raise troops to rendezvous at Portsmouth. Two years later, a French fleet led by Nicholas Béhuchet raided Portsmouth and destroyed most of the town; only the stone-built church and hospital survived. After the raid, EdwardIII exempted the town from national taxes to aid its reconstruction. In 1377, shortly after Edward died, the French landed in Portsmouth. Although the town was plundered and burnt, its inhabitants drove the French off to raid towns in the West Country. Henry V built Portsmouth's first permanent fortifications. In 1416, a number of French ships blockaded the town (which housed ships which were set to invade Normandy); Henry gathered a fleet at Southampton, and invaded the Norman coast in August of that year. Recognising the town's growing importance, he ordered a wooden Round Tower to be built at the mouth of the harbour; it was completed in 1426. Henry VII rebuilt the fortifications with stone, assisted Robert Brygandine and Sir Reginald Bray in the construction of the world's first dry dock, and raised the Square Tower in 1494. He made Portsmouth a Royal Dockyard, England's only dockyard considered "national". Although King Alfred may have used Portsmouth to build ships as early as the ninth century, the first warship recorded as constructed in the town was the Sweepstake (built in 1497). Henry VIII built Southsea Castle, financed by the Dissolution of the Monasteries, in 1539 in anticipation of a French invasion. He also invested heavily in the town's dockyard, expanding it to . Around this time, a Tudor defensive boom stretched from the Round Tower to Fort Blockhouse in Gosport to protect Portsmouth Harbour. From Southsea Castle, Henry witnessed his flagship =Mary Rose sink in action against the French fleet in the 1545 Battle of the Solent with the loss of about 500