On the morning of October 5, 1804, a British naval squadron came across a group of four Spanish frigates off the southern coast of Portugal, close to the port of Cadiz. The two countries were not yet at war, but the British, aware that Napoleon would soon force Spain into a conflict, engaged the Spanish forces, capturing three of the ships, while another, the Nuestra Señora de las Mercedes, sank after her magazine exploded, killing an estimated 265 people and taking a vast hoard of bullion down to the seabed.

And there she would remain, forgotten for more than a century, until US deep-sea treasure hunting company Odyssey located the vessel in 2009 and removed around 600,000 mainly silver coins, along with other items.

When the story broke, the Spanish government of the day, under Socialist Prime Minister José Luis Rodríguez Zapatero, immediately claimed ownership, and the affair soon became a matter of state, rallying the two main political parties in a rare display of unity.

Two new exhibitions in Madrid, one at the National Archeology Museum, and another at the Naval Museum, not only provide historical context to the sinking of the Mercedes, but also tell the story of the legal battle to get the coins returned.

From a legal point of view, the affair ended two years ago after the Supreme Court ruled that as the Mercedes was a warship on a mission of state, the treasure aboard her was Spain’s. Two Hercules military planes were sent to an army base in Tampa to bring the coins back. The Culture Ministry decided that the best place for them to be seen was at ARQUA, the National Sub-Aquatic Archeology Museum in the Mediterranean port city of Cartagena, where a permanent exhibition area has been created.

The exhibition at the Naval Museum tells the story of Diego de Alvear, the second-in-command of the Spanish squadron, whose wife was aboard the Mercedes, along with seven of his children. He was later compensated by the British for his loss. He went on to remarry, tying the knot with an Irishwoman called Lisa Ward, and have another 10 children. One of his sons from his first marriage fought for Argentinean independence a decade later. Several personal items belonging to Alvear are also on show, including his telescope, a portrait of his second wife, a saber and a theodolite. At the time of the encounter with the British, Alvear was returning to Spain with his family, and had been appointed second-in-command of the squadron by José de Bustamante, the commander of the convoy.

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