[3] Their greatest achievements were at the Boyacá (1819), Carabobo (1821), Pichincha (1822) and Battle of Ayacucho (1824) which secured independence for Colombia, Venezuela, Ecuador and Peru from Spanish rule respectively.

South America's wars of independence from Spain provided many of them with an opportunity to continue their military careers and escape from the prospect of inactivity and poverty at home.

Despite Spain and Britain having been allies in the Peninsular War just a few years before, many Britons' image of the Spanish in the Americas was influenced by the now-disputed Black Legend.

Volunteers were also motivated by the liberal propaganda of Simon Bolívar's supporters that portrayed the war as bringing freedom and rights to people under Spanish tyranny.

Mercenary interests also played a large part in motivating potential recruits, who were often unemployed, and perceived South America as a place where they would be able to continue to earn a living.

Pay was to commence upon arrival in Venezuela and when the call was heard on the streets of London thousands began to volunteer for the expedition and soon the first five detachments were formed as follows:[7] The soldiers used Margarita Island as their base.

[8] They took part in the campaign of the Venezuelan Llanos in 1818 and fought at the battles of El Sombrero, La Puerta, Ortiz, Rincón de los Toros and Calabozo.

The first was to be commanded by Colonel Arthur Sandes and the second by Major John Mackintosh who would later become a military aide-de-camp to Simon Bolivar and Antonio Jose de Sucre.

[8] The British Legions after months of inactivity joined Bolivar's army on the Plains of Apure towards the end of 1818 but saw no serious action until March 19, 1819, in a skirmish in the woods of Gamarra.

[16] After the triumphal entry into Santa Fe de Bogota Bolivar credited them with the victory saying "those soldier-liberators are the men who deserve these laurels" [17] They were awarded with the 'Order of the Liberator' one of the rare occasions during the war when this decoration was bestowed onto an entire unit.

With the independence of Colombia and Venezuela secured, Bolivar and his patriot army along with the British Legions moved South to drive the Spanish out of Peru and Ecuador.

The battle could have turned into a rout if the British and Irish troops had not thwarted a dangerous flank attack by the veteran Spanish Aragón battalion.

[23] In the overall strategy British pressure by use of their navy and diplomacy was sufficient to prevent Spain from attempting any serious reassertion of its control over its lost colonies.