In mid-1851 a civil war erupted in Chile following a presidential election in which Manuel Montt defeated José María de la Cruz. Many of Cruz's supporters were sent to the distant penal colony of Magallanes. In November 1851, Lieutenant Miguel José Cambiaso, who was part of the garrison, was jailed for insubordination and subsequently led a bloody mutiny disguised as a revolt by Cruz's supporters. The mutiny is familiar to historians of the period, but what is less well known is the key role played by the British in suppressing it. Contrary to previous historiography, the Chilean government pleaded for British intervention. Given the poor state of the Chilean navy and the precariousness of communications with the penal colony, the Chilean government had no option but to resort to British naval forces. This incident illustrates a new dimension of Anglo-Chilean relations during the mid-nineteenth century which cannot be defined solely as imperialistic; Chilean authorities actively sought cooperation from the British. It also highlights the fragility of the process of state formation in a republic long praised as an example of successful political transition from colony to republic, as well as the lack of commitment of the Chilean government to shoring up state power in Magallanes.