The Treaty of Utrecht reshaped European empires after the War of the Spanish Succession. It granted Britain the Asiento de Negros, a contract to supply enslaved Africans to Spain’s American colonies, plus a limited legal trading right (the navío de permiso). These trade privileges became a long-term source of disputes over smuggling, inspections, and competing imperial control of Caribbean commerce.
Spanish guarda costa (coast guard/privateer) forces boarded the British ship Rebecca and clashed with its captain, Robert Jenkins, during anti-smuggling enforcement. Jenkins later claimed the Spaniards cut off his ear during the incident. The event became a powerful symbol in British politics, used to argue that Spain was attacking British trade rights.
Jenkins appeared before a committee of the British House of Commons and displayed what he said was his severed ear. By this time, many merchants and politicians were already angry about Spanish seizures of British ships and strict inspections. The testimony helped push a trade dispute into a wider public demand for war.
British and Spanish negotiators signed the Convention of Pardo to settle commercial claims and reduce tensions. The agreement was rejected in Britain and never ratified, showing that political support for compromise had collapsed. With the trade dispute unresolved, war became more likely.
Britain formally declared war on Spain, beginning what British writers soon called the War of Jenkins’ Ear (also linked to disputes over the Asiento and Caribbean commerce). The fighting focused on sea power, port cities, and control of shipping lanes rather than large European land battles. The conflict would later merge into the wider War of the Austrian Succession.
A British squadron under Admiral Edward Vernon seized Portobelo (Portobelo/Porto Bello), an important Spanish Caribbean port tied to silver and trade routes. The victory encouraged British leaders to believe that Spain’s American defenses could be broken by rapid naval attacks. It also pushed Britain toward larger, riskier expeditions against major fortified ports.
After Portobelo, Vernon shifted attention to Cartagena de Indias, a heavily defended Spanish port central to regional trade and shipping security. In early 1740, British forces carried out probing operations to test defenses and gather intelligence. These actions set the stage for a much larger combined sea-and-land assault.
In North America, British Georgia’s founder and governor James Oglethorpe attacked St. Augustine to weaken Spanish Florida and secure Georgia’s southern frontier. The siege lasted weeks but ended when Spanish resupply efforts succeeded and British naval support withdrew. The failure showed how hard it was to take Spanish fortifications and sustain operations in the region.
Britain launched its largest campaign of the war: a huge amphibious attack on Cartagena de Indias. Spanish forces, including defenders led by Blas de Lezo and officials in the city, held the fortifications while disease and coordination problems devastated the British expedition. The defeat sharply reduced Britain’s ability to threaten Spain’s main Caribbean ports and shifted the conflict toward smaller raids and wider war priorities.
Spain attempted to invade British Georgia in 1742, seeking to roll back British expansion and protect Florida. Fighting on St. Simons Island culminated in the Battle of Bloody Marsh, where Oglethorpe’s forces and allies stopped the Spanish advance and helped force a withdrawal. The result stabilized the contested border region and reduced the chance of Spain regaining Georgia by force during this war.
Britain tried to damage Spanish-linked commerce by striking ports associated with chartered trade networks, including the Caracas region. At La Guaira, Spanish defenders repelled a British assault, frustrating British plans to disrupt Spanish supply and trade. The battle reflected a shift from grand invasions to smaller, contested actions around ports and shipping routes.
The Treaty of Aix-la-Chapelle ended the War of the Austrian Succession and related wars, including the War of Jenkins’ Ear, largely restoring conquered territories to their prewar owners. For Anglo-Spanish trade conflict, the outcome was mostly status quo—Spain kept its core American port system, and Britain did not achieve the decisive commercial break-through it had hoped for. The war’s legacy was a clearer lesson for both empires: protecting trade meant protecting ports, convoys, and borders across the Atlantic world, not just winning single battles.
War of Jenkins' Ear and Anglo‑Spanish trade conflicts (1739–1748)