The Business of Making Cannons
Posted inKnights of Malta

The Business of Making Cannons

What Malta’s Silent Artillery Tells Us About Early Modern Industry

There’s a row of old cannons sitting on the Birgu waterfront in Malta. Tourists walk past them on their way to the yacht marina. The cannons are black, oxidised, arranged outside what used to be a British naval bakery and before that, the Knights of St John’s shipyard. Most people don’t give them a second look.

But if you want to understand how the early modern economy actually worked—the supply chains, the labour markets, the raw material dependencies that shaped nations—these hunks of metal are as good a place to start as any.

Making a cannon in the sixteenth century was one of the most capital-intensive, technically demanding manufacturing processes in existence. It was the semiconductor fabrication of its era, and only certain places could do it well.

The Geography of Gunfounding

Here’s something that might surprise you: Malta couldn’t really make its own cannons. Not the good ones, anyway.

The premium gun-founding centres of the sixteenth century were concentrated in a handful of locations:

  • Northern Italy — Venice and Milan especially — had been casting bronze since the Renaissance and understood metallurgy in ways that took other regions centuries to replicate
  • Flanders — another established centre with skilled craftsmen and supply networks
  • Nuremberg — German expertise in metalworking translated directly to ordnance

These places had the skilled labour, the established supply chains, and the accumulated know-how that gun-founding required.

The Knights of St John, who controlled Malta from 1530, were customers in this market, not manufacturers. When they needed bronze cannon—the expensive, reliable kind—they bought Italian. The Venetian sacre from around 1510 that sits in Malta’s Maritime Museum collection came from this trade network.

What Malta could produce locally were cheaper, cruder weapons. The arsenals at Birgu and later Valletta turned out wrought-iron pieces using an older construction method: iron staves bound together with hoops, like a barrel. This “hoop and stave” technique was already considered archaic by 1565. It worked, sort of, but the guns were:

  • Heavier than cast bronze equivalents
  • Less accurate
  • More prone to failure

Why Bronze Cost So Much

A bronze cannon wasn’t just expensive because bronze is shiny. The economics were demanding at every stage.

Raw Materials

Bronze is an alloy of copper and tin, and both metals had to travel long distances to reach a Mediterranean island with no meaningful mineral deposits.

  • Copper came from mines in Central Europe, Scandinavia, and by the seventeenth century, even Japan
  • Tin was scarcer, sourced mainly from Cornwall and parts of Germany

Everything had to be imported by sea, which meant:

  • Shipping costs
  • Insurance against loss
  • Constant risk that conflict would cut off your suppliers entirely

For more on how the Knights managed these complex economic challenges, see The Economics of the Knights of Malta.

The Casting Process

Bronze cannon were made by pouring molten metal into clay moulds suspended vertically in pits, usually breech-down so the thickest, strongest metal settled where the pressure was greatest during use.

The process demanded extreme precision. Air bubbles, impurities, or uneven cooling could create weaknesses invisible to the eye but dangerous when the piece was actually used. Quality control was literally a matter of life and death for the operators.

Skilled Labour

Gun founders were specialised craftsmen, trained over years, commanding premium wages. They moved across borders for work:

  • Swiss founders worked in France and Spain
  • Dutch founders, trained by the Swiss, worked in England
  • Monarchs competed to attract and retain these workers

The knowledge was valuable enough that it transcended national loyalties.

Bronze vs Iron: The Numbers

According to research published in the Journal of Global History, cast-iron cannons—which England began producing successfully in the 1540s—cost three to four times less than bronze equivalents.

But iron had drawbacks:

  • Significantly heavier
  • Less reliable over time
  • A reputation for problems under intensive use

European state navies were slow to adopt iron. Bronze remained the prestige material, the choice when reliability mattered more than budget.

The Workforce Question

Like most large-scale enterprises of the period, the Order’s operations in Malta relied on a mixed workforce.

Skilled work required paid craftsmen—bombardiers and specialists who commanded market wages. But the heavy labour that kept arsenals and shipyards functioning often fell to unfree workers, including captives taken during the endemic Mediterranean conflicts of the era.

A 2020 academic study of material culture in Malta between 1600 and 1900 documents how this labour was integrated into the Order’s dockyard economics. This wasn’t unique to Malta—coerced labour was widespread across the Mediterranean world—but it’s part of the economic picture that made large-scale military production possible in this period.

The corsairing economy that supplied much of this labour was itself a major driver of Malta’s finances during the Knights’ era.

Propellant: The Consumable Problem

Artillery required propellant, and propellant was its own industrial challenge.

The Order established windmills around Malta from as early as 1533 specifically for this purpose. These were dual-use facilities—grinding grain for bread while also processing materials for military use. A 2014 study on Maltese manufacturing documents this integration of civilian and military infrastructure.

Some raw materials could be sourced locally, but key components had to be imported, usually from Sicily or further afield. This created the same vulnerability that plagued cannon manufacturing itself: dependence on supply chains that adversaries could disrupt.

State Control

The Order maintained a state monopoly on production:

  • Mills were mapped and regulated
  • Positioned away from population centres for safety
  • Subject to strict oversight

The Treasury System: How the Order Paid for All This

Military hardware is expensive. The Knights’ solution was a sophisticated treasury system that pooled resources from across their European network. For a deeper look at their financial innovations, see How the Knights Mastered Medieval Wealth.

Revenue Sources

The Order drew income from “commanderies”—landed estates scattered across Catholic Europe that Knights administered and taxed. Studies of the Order’s Common Treasury suggest that between 20 and 33 percent of these revenues were earmarked for military expenditure, including artillery acquisition and maintenance.

This financial system was part of a broader medieval financial revolution that allowed organisations like the Order to operate across national boundaries.

Estate Reversion

There was also another funding mechanism: when a Knight died, his personal estate reverted to the collective treasury.

  • No private inheritance of Order assets
  • No selling off of military equipment
  • The cannons belonged to the Order as an institution, not to individuals

This prevented the fragmentation of military capability that plagued feudal armies and ensured a steady stream of capital for procurement.

Fiscal Discipline

The system was rigid by design:

  • Knights faced restrictions on personal investments that might drain collective funds
  • Fiscal discipline was enforced through serious penalties

Whatever else you might say about the Knights, they understood institutional economics. The same financial discipline that paid for cannons also funded the massive fortification programme that transformed Malta’s landscape.

What the British Found, and What They Did With It

When Britain took control of Malta following the French invasion of 1798, approximately 350 bronze cannons existed across the islands.

The British, with the pragmatism of an industrial power, recycled most of them.

This wasn’t destruction for its own sake—it was resource recovery. Bronze was valuable. Old cannons, regardless of their historical interest, were raw material. The practice had precedent: throughout the early modern period, obsolete and captured cannons were routinely recast into new equipment.

A Spanish piece from 1747 in Fort Ticonderoga’s collection bears the inscription “Bronzes Viexos”—old bronze—indicating it was cast from melted-down predecessors.

About thirteen bronze pieces survived in Malta. The ones sitting on the Birgu waterfront today are remnants of a remnant.

The New Economy

Under British rule, Malta’s military economy shifted:

  • The dockyards became major employers — at some points roughly 20 percent of the Maltese workforce
  • Work shifted to maintenance and repair for a steam-powered industrial navy
  • Wages came from Admiralty funds in London
  • The local economy became dependent on British military spending

This dependency persisted well into the twentieth century, shaping Malta’s economy through two world wars and beyond.

What These Cannons Actually Tell Us

The cannon was the defining military technology of early modernity, and its manufacturing requirements shaped states. Only governments—or quasi-governmental entities like the Knights of St John—could marshal the capital, the supply chains, and the skilled labour that production demanded.

This wasn’t an accident. It was a structural feature of the technology.

The cannons on the Birgu waterfront are industrial artifacts as much as military ones. They represent:

  • Supply chains stretching from Cornish tin mines to Venetian foundries to Maltese arsenals
  • Labour markets that crossed national boundaries
  • Treasury mechanisms designed to fund continuous investment across centuries

They also represent obsolescence. The technology that made these objects cutting-edge was eventually superseded—rifled barrels, new loading mechanisms, industrial-scale metal production.

The same pressures that created them—the economics of competition—eventually rendered them museum pieces.

Walk past them on your way to the marina if you want. But understand what you’re walking past.

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References

  • Guilmartin, John Francis. Gunpowder and Galleys: Changing Technology and Mediterranean Warfare at Sea in the Sixteenth Century. Cambridge University Press, 1974; revised edition, Naval Institute Press, 2003.
  • Catania, J.A. et al. Captives, Colonists and Craftspeople: Material Culture and Institutional Power in Malta, 1600–1900. Berghahn Books, 2020.
  • Caruana, C. “Windmills and the Production of Gunpowder in Malta.” Academia.edu, 2014.
  • Cassar Pullicino, J. “The Treasury, Debts and Deaths: A Study of the Common Treasury of the Order of St John.” Academia.edu, 2015.
  • Spiteri, Stephen C. Armoury of the Knights. Midsea Books, 2003.
  • “Contractor States and Globalization of the Market for Naval Artillery Technology (1500–1750).” Journal of Global History, Cambridge University Press, 2024.
  • Czerwinski, A. and Zygulski, Z. “The Palace Armoury of Valletta.” UNESCO, 1969.
  • “Metallurgy of Armour Exhibited at the Palace Armoury Valletta, Malta.” ResearchGate, 2004.