HMNB Portsmouth: Where the Mary Rose Sank and the Industrial Revolution Quietly Began

Eight Centuries of Naval History, Give or Take

Portsmouth's naval story is generally dated to 1194, when Richard I granted the town its first Royal Charter, an act widely credited with founding what would become Britain's premier naval port, with protective walls added under King John in 1212.

The pivotal early development came under Henry VII, who in 1495 and 1496 ordered the construction of what is usually described as the world's first dry dock, though some sources more cautiously phrase this as the oldest surviving dry dock, a small but genuine distinction worth keeping in mind, since being first and being the oldest still standing are not quite the same claim.

The Mary Rose, and a Death Nobody Can Fully Explain

Henry VIII made Portsmouth home to a permanent standing navy, and it was here, on 19 July 1545, that his flagship the Mary Rose sank in the Solent during the Battle of the Solent against an invading French fleet, taking roughly five hundred of her seven hundred crew down with her.

Why she sank remains particularly disputed among historians even today, with the Mary Rose Trust itself declining to declare a single winner among the leading theories, which include an ill-timed turn that left her open lower gunports exposed to a sudden gust of wind, inexperienced command, simple overloading, and, less credibly, French cannon fire.

She was finally raised on 11 October 1982 after 437 years underwater, and following a thirty-year conservation effort the museum built to house her now displays more than nineteen thousand Tudor artefacts, billed as the largest collection of its kind anywhere in the world.

The Machines That Quietly Started the Industrial Revolution

Portsmouth's most historically significant achievement may not be a ship at all. From 1802, engineer Samuel Bentham commissioned a scheme designed by Marc Isambard Brunel and built by Henry Maudslay to mechanise the production of wooden pulley blocks, the simple but essential rigging components every warship needed by the thousand.

Installed in stages between 1803 and 1807, the resulting Portsmouth Block Mills used forty-five machines and largely unskilled labour to produce some 130,000 blocks a year by 1808, dramatically outstripping previous Navy demand of around 100,000 annually, and the achievement is widely regarded by historians of technology as one of the true starting points of mechanised mass production.

One figure makes the case better than the output does. It was claimed at the time that ten unskilled men using the machines could replace one hundred and ten skilled blockmakers. That ratio is the industrial revolution in a single line, and it happened in a naval dockyard rather than in a textile mill, for the very ordinary reason that the Navy needed a great many identical small wooden objects and could not get them fast enough.

What was genuinely new was not the mechanisation but the material. Machines had been mechanising things for decades; what Maudslay built at Portsmouth was the first use anywhere in the world of all-metal machine tools for mass production. A wooden machine flexes and wears and cannot hold a tolerance. A metal one can, and once it can, interchangeable parts become possible, and once those are possible everything else follows.

And they did not stop. Block production at Portsmouth carried on until the 1960s, which means machine tools installed while Nelson was still alive were earning their keep in a dockyard that was by then handling nuclear submarines. Some of the original machines, parts of the transmission drives and the engine house shells are still in the buildings.

In a nice piece of local colour, Marc Brunel's own son, Isambard Kingdom Brunel, was born just a few hundred yards away in Portsea in April 1806, while his father was still building the very machines that would help define the industrial age his son went on to shape. HMS Victory, completed in 1765 at a cost of some sixty-three thousand pounds, went on to become Nelson's flagship at Trafalgar in 1805, where she suffered fifty-one men killed in action and a further eleven who later died of their wounds, and Nelson himself reportedly toured the newly built Block Mills shortly before his final departure aboard her.

It is worth saying what HMS Victory still is, because visitors often assume she is a museum ship. She is a commissioned warship of the Royal Navy, has been continuously since 1778, and is the flagship of the First Sea Lord. That makes her the oldest commissioned warship in the world, and it is why she flies a White Ensign rather than a museum flag. She has sat in No. 2 Dock since 1922, which is itself now over a century, and the dock she sits in is a descendant of the one Henry VII ordered in 1495.

Blitz, and the Push Toward D-Day

The nineteenth century brought steam-age transformation and a vast programme of basin extensions, along with HMS Warrior, launched in 1860 and described by naval historians as the Royal Navy's first iron-hulled armoured warship and the most powerful warship of her day.

How HMS Warrior came to be lying in Portsmouth at all is a story of its own. She was made obsolete inside a decade by the very pace of change she had started, was reduced to a depot ship and then a torpedo school, and finally spent fifty years as an oil jetty at Milford Haven, with oil pipes running through her and her masts long gone. An eight-year restoration at Hartlepool brought her back, and she returned to Portsmouth in 1987. She is under a long conservation programme now, which is what happens to an iron ship that has spent a century and a half in salt water.

The Second World War hit Portsmouth hard, with the city enduring some sixty-seven separate air raids between 1940 and 1944, killing 930 people and injuring a further 2,837, destroying or severely damaging roughly a fifth of the city's housing stock.

The single worst night came on 10 and 11 January 1941, when around three hundred bombers dropped 140 tons of high explosive and some forty thousand incendiaries, killing 171 people and destroying both the Guildhall and the Royal Garrison Church, the latter deliberately left roofless ever since as a permanent memorial.

Just over three years later Portsmouth became a critical embarkation hub for D-Day, with more than 170,000 troops and around 43,000 tanks and vehicles departing through the city, while the dockyard itself helped build the vast concrete Phoenix caissons used in the Mulberry harbours off the Normandy beaches.

The Falklands, and the Fleet Today

Portsmouth's more recent history includes the departure of the Falklands Task Force, which began sailing from the city on 5 April 1982, just three days after the Argentine invasion, eventually growing into a force of 127 ships carrying around nine thousand personnel, led by the carrier HMS Hermes, which had ironically been due for decommissioning before the war intervened.

Today HMNB Portsmouth is home to almost two-thirds of the Royal Navy's surface fleet, including both Queen Elizabeth-class aircraft carriers, HMS Queen Elizabeth, which arrived in 2017, and HMS Prince of Wales, which followed in 2019, alongside the Type 45 destroyer and Type 23 frigate fleets.

While Portsmouth is unquestionably the Royal Navy's oldest and most historically significant base, it is worth noting that Devonport remains the physically larger of the two, a useful corrective for anyone tempted to assume Portsmouth's fame automatically makes it the biggest.

The two bases have also specialised in opposite directions, which is the more useful distinction. Portsmouth is a surface fleet base: the carriers, the Type 45s and the frigates, with no submarine work at all. Devonport is where the submarine refitting is done, along with amphibious and survey ships, and it has the deep-maintenance facilities Portsmouth does not. One is where the fleet lives and the other is where it is taken apart and put back together.

The Falklands departure of 1982 makes the point about Portsmouth rather well. HMS Hermes sailed from here on 5 April 1982, three days after the invasion, having been due for disposal, with dockyard workers still aboard finishing off as she went down harbour. That is what an operational base a few hundred yards from a Tudor dry dock is actually for.

What notably sets Portsmouth apart is the unusual and rather wonderful arrangement by which a fully working, operational naval base sits immediately alongside Portsmouth Historic Dockyard, where visitors can walk past HMS Victory, HMS Warrior and the Mary Rose Museum within sight of the modern warships still doing the job those older vessels once did themselves.

Project Royal Oak

In July 2026, Portsmouth was allotted £3.9 billion of Project Royal Oak, the ten-year, £26 billion programme announced by defence minister Luke Pollard to rebuild the three main naval bases, the largest such investment since the end of the Cold War. The money is for a major renewal of the waterfront, upgrades to docking and port infrastructure, modernised operational facilities, estate improvements for the surface fleet and new and refurbished accommodation: the unglamorous groundwork a base needs if it is to keep two carriers and most of the surface fleet running for another generation.

This is a live article which will be updated when more information is available.