The Battle of Porto Bello occurred as part of the larger context of the War of Jenkins' Ear, which stemmed from escalating tensions between Britain and Spain over trade and territorial disputes in the Caribbean and North America. The conflict began after the Spanish seized British ships and mistreated merchants, prompting calls for action from London. Admiral Edward Vernon, an influential figure in the British Navy, took command of a fleet destined for Porto Bello, a strategically important port city in the Spanish Empire.

On the day of the battle, Vernon led a fleet of six warships and a number of smaller vessels to lay siege to the port, which was heavily fortified and defended by Spanish soldiers. The British forces commenced bombardment on the fortified positions of Porto Bello, which included three forts and numerous defensive structures. The defenders, numbering around 1,500 Spanish troops, held their positions initially but could not withstand the sustained British naval bombardment.

Vernon's forces executed a coordinated attack, using their superior naval artillery and tactics. After several days of fighting, the Spanish commander, Manuel de Saldana, ultimately surrendered Porto Bello on November 23, 1739. This swift victory heightened British morale and demonstrated the capabilities of their naval forces, while simultaneously straining Spanish resources and signaling a shift in power dynamics in the Caribbean.