Brown, William (1777–1857), merchant captain and first admiral-in-chief of the Argentine navy, was born 22 June 1777 in Foxford, Co. Mayo. (John De Courcy Ireland has suggested that Brown was the extramarital son of a Roman catholic woman from Foxford and George Browne (c.1735–1782), collector of revenue for the Foxford district 1756–69, MP for Mayo 1779–82, and brother of Peter Browne-Kelly (1731–80), 2nd earl of Altamont; however, it is unlikely that George Browne ever resided in Foxford.) William Brown appears to have been one of four full siblings. After receiving some education, he left Ireland in the late 1780s to serve as a midshipman in the British navy, rapidly transferring to the merchant marine, and then probably serving on a privateer in the West Indies. By 1806 he was a master mariner in command of merchant ships on Atlantic routes. Late in 1811 he settled in Buenos Aires just as a criollo rebellion against Spanish colonial rule in Argentina was gaining strength. By April 1812 he was developing a coastal shipping business in fruit and hides. As the Spanish naval blockade of 1812–14 began to choke trade, he was first commissioned by the patriot government as a privateer licensed to raid Spanish merchantmen, and then (1 March 1814) invited to take charge of a small rebel naval squadron to contest Spanish control of the River Plate estuary. Leading a fleet of nineteen ships, he fixed with great speed on a set of wartime naval routines and signalling methods, and organised a system of discipline, founding the navy on principles that paid exceptional attention to the welfare of ordinary seamen. In early March 1814 he showed personal courage and incisive skill in outwitting and defeating a more powerful Spanish force near the island of Martin Garcia, thereby dividing the Spanish blockade. A Spanish attempt (May 1814) to break his blockade of Montevideo was decisively crushed by Brown and his makeshift navy, and the Spanish strongholds on the Atlantic coast collapsed, ending open war. In 1815 and 1816, however, Brown carried out skirmishing raids on military and commercial targets belonging to Spanish South American possessions, until detained by a British colonial governor in Barbados (July 1816) for alleged infringements of international rules of trade. Illness, and a tortuous but ultimately successful appeal process, took up most of 1817–18, but when he returned to the United Provinces (Argentina) in October 1818, political enemies set in motion a prosecution for alleged disobedience of orders. Cashiered in August 1819, then restored in rank but forced to retire, he attempted suicide the following month. Convalescence and resumption of his trading concern occupied several years.
A repentant government renewed his command of the navy in December 1825, when war broke out with Brazil. Though vastly outnumbered by the Brazilian fleet, he showed audacity and great finesse in a number of successful engagements in the Plate estuary in 1826, roving up the Brazilian coast on occasion to create great confusion. In February 1827 he triumphed in a series of actions known as the battle of Juncal. After another year of commercial privateering against the Brazilian merchant fleet, he was one of two delegates selected to sign peace terms with Brazil (October 1828). Retiring from active service that month, he tried to remain neutral as civil war erupted in the United Provinces, reluctantly accepting the post of governor of Buenos Aires under Gen. Lavalle from December 1828 to May 1829, when he resigned in disgust at government excesses. During 1829–37 he held aloof from the despotic government of Manuel Rosas. After French and British encroachments on the region in the later 1830s, he offered to take charge of the navy again to protect national independence, and was available to defend Argentine interests when war broke out with a French-backed Uruguay in early 1841. Though exasperated by a long and ‘stupid war’ (De Courcy Ireland (1995), 117), he blockaded the Uruguayan navy effectively until French and British fleets intervened in July 1845 with overwhelming force to capture his squadron and bring the war to an end. Idolised by the Argentinian population for his high-principled and humane advocacy of independent democracy, he passed his last years trading and farming a country estate. In late 1847 he journeyed to Ireland, hoping to find relations in Mayo, and was shocked by the hunger and destitution of the great famine. He died on 3 March 1857 at his home in Buenos Aires.
He married (July 1809) Eliza Chitty of Kent, daughter of an English shipping magnate. Despite lengthy periods of enforced separation, they had nine children.