[3] Lezo's defense of Cartagena de Indias against Vernon's vastly larger force consolidated his legacy as one of the most prominent military commanders in the history of Spain.

[4][5] Born in Pasajes (at that point still part of San Sebastián), in the Basque Province of Guipúzcoa in Spain, Blas de Lezo y Olavarrieta attended school in France and commenced his naval career in the Franco-Spanish fleets, then united by the Bourbon alliance of the War of Spanish Succession, in 1701 as a midshipman.

In 1704, he fought in the War of the Spanish Succession as a crew member in the Franco-Spanish fleet against the combined forces of Great Britain and the Netherlands at the indecisive Battle of Vélez-Málaga.

[8][9] Modern sources often focus on these salient features and refer to de Lezo with nicknames such as "Patapalo" (Pegleg) and "Mediohombre" (Half-man).

In 1732, on board the Santiago, he and José Carrillo de Albornoz commanded the enormous expedition to Oran and Mers-el-Kébir with more than 300 ships and around 28,000 troops, comprising infantry, cavalry and artillery.

In the following months he established a naval blockade, preventing the Algerians from receiving reinforcements from Istanbul and thereby gaining valuable time for the securing of Oran's defense, until an epidemic forced him to return to Cádiz.

He returned to South America with the ships Fuerte and Conquistador in 1737 as General Commander of the Spanish fleet stationed at Cartagena de Indias, in modern-day Colombia.

One such attack involved the capture of Portobelo (Panama), the dismantling of its fortifications and the subsequent withdrawal of British forces having left the place defenceless.

Both Vernon and Edward Trelawny, the British governor of Jamaica, considered the Spanish gold shipping port to be a prime objective.

Vernon's intention was to gather information on the city's topography and troop strength and to provoke a response that might give him a better idea of the defensive capabilities of the Spanish.

The defences of Cartagena de Indias comprised between 3,000 and 6,000 combatants, including regular troops, militia, and native archers, and six Spanish ships of the line and their crews.

Three columns of grenadiers supported by Jamaicans and several British companies moved under cover of darkness, with the aid of an intense naval bombardment.

There was a spate of impressionistic and highly inaccurate novels following the publication by the Colombian historian Pablo Victoria of his fictional biography of Lezo: