The issue of sulfur was a political crisis between the Kingdom of the Two Sicilies and the United Kingdom. Development
Sicily owned 90% of the world reserves of sulfur, an essential mineral for the chemical industry of the time, particularly that of explosives.
In 1816 a treaty of commerce was signed between London and Naples and quickly the British merchants hastened to buy advantageously almost all the sulfur production of the island. Fernando II decided to neutralize the situation by granting the sulfur trade to a French commercial company, which offered to pay twice as much as the British.
Relations between the United Kingdom and the Two Sicilies deteriorated, and Prime Minister Lord Palmerston decided to send a war fleet to the Gulf of Naples. Fernando II ordered the general mobilization in anticipation of an attack, with the support of Austria, but this denied its support to the southern kingdom.
Fernando II was forced to sign a treaty that canceled the contract with the French company and to pay for the British economic losses during the period it had lasted.
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