In October 1834 he was appointed Military Governor of Arequipa, Puno, and Cuzco; and it was at this time that he conceived the idea of forming a military colony in the valleys to the eastward of Cuzco, on the banks of some of the tributaries of the great river Purus. In March 1835, while on the point of setting out on an exploring expedition, a revolution broke out in Cuzco, and he was arrested by Colonel Lopera. He was, however, allowed to set out on his expedition, with two companions and seven Indians. He penetrated on foot to a greater distance to the eastward of Cuzco, on this occasion, than has ever been done before or since.
In September 1835 he again placed himself under the orders of the Constitutional President Orbegoso, and in February 1836 he captured Salaverry and eighty officers of his revolutionary army by a very clever stratagem, near Islay. Shortly afterwards Santa Cruz established the Peru-Bolivian Confederation, and General Miller was sent as Minister Plenipotentiary to Ecuador, where he signed a treaty of peace and amity between that Republic and the Confederation. In August 1837 he became Governor of Callao, when all customs duties were reduced one half, smuggling ceased, and the receipts were soon quadrupled. He organized an efficient police; made a subterraneous aqueduct 3 feet wide, 3½ deep, and 280 yards long, for supplying Callao with water; commenced the erection of a college; and formed a tramway for the conveyance of goods from the mole to the custom-house. The people of Callao still look back with satisfaction and gratitude to the period when General Miller was their Governor.
In February 1839, on the overthrow of the Peru-Bolivian Confederation, General Miller was banished with many other able and distinguished men, whose names were taken off the army list by a decree dated in the following March. This unjust and illegal act was cancelled by a law of Congress dated October 1847.
After leaving Peru in 1839, General Miller was appointed in 1843 H. M. Commissioner and Consul-General for the Islands in the Pacific. In 1859 he revisited Chile and Peru, partly for his health, and partly to obtain the payment of his large arrears from the Government. When he arrived in Peru the Vice-President Mar, while the President, General Castilla, was absent at Guayaquil in 1859, reinstated him on the army list of Peru, by a decree dated December 9th, the anniversary of the battle of Ayacucho, and granted him his current pay as a Grand Marshal of Peru, and he continued to reside at Lima until his death on the 31st of October 1861. It is satisfactory to be able to record, for the honour of the Peruvian nation, that the whole of his claims were acknowledged in Congress in a most handsome way, and without a dissentient voice. But unfortunately the executive in Peru is still able to set the laws passed by the representatives of the people at defiance; delays and evasions were resorted to by Castilla, and the last days of one from whom Peru had perhaps received as valuable services as from any of her own sons, were embittered by the treatment which he experienced from the President of the Republic.
General Miller was a man of whom England may well be proud. He was one of those characters who combine great ability and extraordinary daring, almost amounting to rashness, with modesty and diffidence. If there was any fault to be found in any part of General Miller's former career, in the camp or in the cabinet, it would be from himself that it would first be heard. To his bravery and prowess, his body riddled with bullets, and the history of South American independence, bear testimony; to his administrative ability the gratitude of the people of Callao and Cuzco is the witness; his pure standard of honour, his scrupulous integrity, his warmth of heart, and single-mindedness are known to a wide circle of sorrowing friends; but of his numerous acts of self-denial and charity few can tell, for he was one who let not his left hand know what his right hand did.
In person he was more than six feet high, and when young he was remarkably handsome; his features and shape of the head being of a thoroughly English type. In society he was exceedingly agreeable to the last; his conversation was always interesting, and often very instructive; and there was a peculiarly gentle and winning expression in his eyes. He took a deep interest in the attempt to introduce chinchona cultivation into India, and I was indebted to him for much valuable advice, and for many letters of introduction which were of great service to me. He also supplied me with most of the material which has enabled me to write the narrative of the insurrection of Tupac Amaru, the last of the Incas, forming the ninth chapter of the present work.
His memoirs, published by his brother many years ago, give by far the fullest and most interesting account of the war of independence in Chile and Peru, though the work of Garcia Camba, a Spanish general, is the best military history.
General Miller breathed his last on board H.M.S. 'Naiad' in Callao Bay, on the 31st of October 1861; and the remains of the gallant old warrior were interred in the cemetery at Bella Vista, with all the honours which the Peruvian Government could bestow. While the body was being embalmed, two bullets were found in it, and twenty-two wounds were counted on different parts of his frame. The most gratifying incident on the occasion was that the people of Callao, who had never forgotten the good he had done them as their Governor, insisted on carrying the coffin.
One of the last things on which General Miller was employed was the compilation of the list of his brave companions in arms. Such a list, I believe, has never appeared before; and as the employment interested and amused him during a time of much harassing annoyance, it gives me great pleasure to be able to insert it here, in order that his labour may not have been entirely in vain.