On 12 January 1839 a squadron of privateers sailing for the Peru-Bolivian Confederation attacked three Chilean warships anchored in the bay of Casma, on the coast of northern Peru. The Chileans, commanded by Robert Simpson, an English-born officer in the Chilean navy, beat off the attack after a hard fight at close range. The privateers' commander, Blanchet, was killed. Eight days later the Chilean-led army won the Battle of Yungay, which ended the war.
A war over the Confederation
The Bolivian leader Andrés de Santa Cruz had joined Peru and Bolivia in the Peru-Bolivian Confederation. Chile saw the new state as a threat, and Memoria Chilena, the Chilean National Library's history portal, records that the Chilean government decided to break up the Confederation by force of arms. In 1838 Chile sent its army into Peru under General Manuel Bulnes.1
At sea Santa Cruz tried to rebuild the Confederation's naval power with privateers, as Gonzalo Bulnes describes. Bulnes names their commander only as Blanchet. A painting of the battle held by Chile's National Museum of Fine Arts is catalogued as a fight between Chilean ships and French privateers in the service of the Confederation.2
The fight in the bay
Simpson's three ships, the Confederación, the Valparaíso and the Santa Cruz, were at anchor in Casma Bay, north of Callao, while a transport took on firewood. Four privateers came in to attack them: the Edmond, the Mexicana, the Arequipeño and the Perú.3
The most detailed account comes from the Chilean historian Gonzalo Bulnes, whose history of the campaign appeared in 1878. The privateers came into the bay at about five in the afternoon. The Arequipeño and the Edmond, at the head of the line, came in so fast that they could not stop in time and ran foul of the Confederación; the Arequipeño then became entangled with the Santa Cruz as well. Their crews tried to board, but the fire of the Chilean sailors and soldiers drove them back. After about an hour and a half of fighting, with Blanchet dead, the other privateers fled and left the Arequipeño, still caught against the Santa Cruz, in Chilean hands.4
Losses and the result
Bulnes gives the privateers' losses as the commander of the Arequipeño and 13 of her crew killed and 70 men taken prisoner, together with the captured brig. Those figures leave out the dead and wounded aboard the ships that escaped, so the real losses were higher.5
The surviving privateers made for Callao, where, Bulnes writes, they were disarmed to be taken to Guayaquil under the French flag. Memoria Chilena lists 12 January 1839 as a naval victory over the Peru-Bolivian squadron at Casma under Captain Roberto Simpson. Chile kept control of the sea for the rest of the war. For more fights at sea, see our guide to the greatest naval battles.6
Yungay and after
On 20 January 1839 Bulnes's army defeated Santa Cruz at Yungay, as both Memoria Chilena and EBSCO record. Santa Cruz went into exile, as EBSCO notes, and Memoria Chilena dates the decision to dissolve the Confederation to March 1839.7 › Battle of Yungay, 1839
Simpson, born in England in 1799, was rewarded for Casma. The Chilean Congress library's biography says he received a gold medal and promotion to the rank of capitán de navío. He died in Valparaíso in December 1877.8
