In late 1796, with the French Revolutionary Wars three years old, a major shift occurred in the conflict when the Kingdom of Spain, until that point an enemy of the French Republic, abruptly changed sides following the signing of the Treaty of San Ildefonso.[1] This reversal forced the British Royal Navy to retire from the Mediterranean Sea to preserve its lines of communication, falling back to the mouth of the Tagus River near Lisbon. From the Tagus, pressure was placed on the Spanish Navy by the erstwhile British Mediterranean Fleet under Vice-Admiral Sir John Jervis, who organised a blockade of the main Spanish fleet base at Cádiz on the country's Southern Atlantic coast.[2] This resulted in the Battle of Cape St. Vincent on 14 February 1797, when Jervis inflicted a stinging defeat on the Spanish fleet. The surviving Spanish ships limped back to Cádiz after the battle, and to ensure that they could not sail again without risking risking a repeat action, Jervis arranged a close blockade of the port so that by April there were 21 British ships of the line and numerous frigates watching the Spanish fleet at anchor.[3]

The blockade of Cádiz was designed not only to contain the main Spanish fleet, but also to disrupt Spanish communications and transport. Cádiz was the principal port of Southern Spain and thus an important destination for shipping from across the Spanish Empire. This included numerous so-called "treasure ships", heavily armed warships that convoyed the gold and silver from the Spanish colonies in the Americas to the Spanish mainland.[4] For centuries, Spanish treasure ships had been the ultimate prize for Royal Navy captains, and the sums of prize money involved were enormous. In October 1799, a Spanish treasure convoy was captured off Vigo and the British captains alone were awarded £40,730 each (the equivalent of £5,054,600 as of 2024).[5][6]

The blockade of Cádiz remained in force with varying degrees of intensity for the remainder of the year, with the British fleet retiring to the Tagus during the winter.[7]

  • Adkins, Roy & Lesley (2006). The War for All the Oceans. Abacus. ISBN 0-349-11916-3.
  • Clowes, William Laird (1997) [1900]. The Royal Navy, A History from the Earliest Times to 1900, Volume IV. Chatham Publishing. ISBN 1-86176-013-2.
  • Gardiner, Robert, ed. (2001) [1996]. Nelson Against Napoleon. Caxton Editions. ISBN 1-86176-026-4.
  • James, William (2002) [1827]. The Naval History of Great Britain, Volume 2, 1797–1799. Conway Maritime Press. ISBN 0-85177-906-9.
  • Maffeo, Steven E. (2000). Most Secret and Confidential: Intelligence in the Age of Nelson. London: Chatham Publishing. ISBN 1-86176-152-X.
  • Rose, J. Holland (1924). "Napoleon and Sea Power". Cambridge Historical Journal. 1 (2): 138–157.
  1. ^ Henderson, p. 104
  2. ^ Gardiner, p. 120
  3. ^ Gardiner, p. 132
  4. ^ Cite error: The named reference RW99 was invoked but never defined (see the help page).
  5. ^ UK Retail Price Index inflation figures are based on data from Clark, Gregory (2017). "The Annual RPI and Average Earnings for Britain, 1209 to Present (New Series)". MeasuringWorth. Retrieved May 7, 2024.
  6. ^ Henderson, p. 106
  7. ^ Gardiner, p. 135