At the age of sixteen he ran away from home and enlisted in the British army. For this violation of its principles he was disowned by the Society of Friends, but his father bought him a commission, dated July 3, 1800, in the 13th (Somersetshire) Light Infantry. He served in the demonstration against Ferrol, and in the expedition to Egypt under Sir Ralph Abercromby in 1801. After the expulsion of the French from Egypt he returned home, but came back to the Mediterranean in 1805 among the troops sent to defend the island of Sicily. He accompanied the expedition which landed in Calabria, and fought a successful battle against the French at the Battle of Maida on July 6, 1806. Church was present on this occasion as captain of a recently raised company of Corsican Rangers. His zeal attracted the notice of his superiors, and he had begun to show his capacity for managing and drilling foreign levies. His Corsicans formed part of the garrison of Capri from October 1806 till the island was taken by an expedition directed against it by Murat, in September 1808, at the very beginning of his reign as king of Naples. Church, who had distinguished himself in the defence, returned to Malta aftel the capitulation.
In the summer of 1809 he sailed with the expedition sent to occupy the Ionian Islands. Here he increased the reputation he had already gained by forming a Greek regiment in English pay. It included many of the men who were afterwards among the leaders of the Greeks in the War of Independence. Church commanded this regiment at the taking of Santa Maura (now Lefkada), on which occasion his left arm was shattered by a bullet.
During his slow recovery he travelled in northern Greece (Macedonia), and to Constantinople. In the years of the fall of Napoleon (1813 and 1814) he was present as English military representative with the Austrian troops until the campaign which terminated in the expulsion of Joachim Murat from Naples. He drew up a report on the Ionian Islands for the congress of Vienna, in which he argued in support, not only of the retention of the islands under the British flag, but of the permanent occupation by Britain of Parga and of other formerly Venetian coastal towns on the mainland, then in the possession of Ali Pasha of Jannina. The peace and the disbanding of his Greek regiment left him without employment, though his reputation was high at the war office, and his services were recognized by the grant of a companionship of the Bath.
In 1817 he entered the service of King Ferdinand of Naples as lieutenant-general, with a commission to suppress the brigandage then rampant in Apulia. Ample powers were given him, and he attained a full measure of success. In 1820 he was appointed governor of Palermo and commander-in-chief of the troops in Sicily. The revolution which broke out in that year led to the termination of his services in Naples. He escaped from violence in Sicily with some difficulty. At Naples he was imprisoned and put on his trial by the government, but was acquitted and released in January 1821 ; and King George IV conferred on him a knight commandership of the Hanoverian order.
The rising of the Greeks against the Turks, which began at this time, had his full sympathy from the first. But for some years he had to act only as the friend of the insurgents in England. In 1827 he took the honorable but unfortunate step of accepting the commandership-in-chief of the Greek army. At the point of anarchy and indiscipline to which they had now fallen, the Greeks could no longer form an efficient army and looked for salvation to foreign intervention. Sir Richard Church, who landed in March, was sworn archistrategos on April 15, 1827. But he could not secure loyal co-operation or obedience. The rout of his army in an attempt to relieve the Acropolis of Athens, then besieged by the Turks, proved that it was incapable of conducting regular operations. The acropolis capitulated, and Sir Richard turned to partisan warfare in western Greece.
Here his activity had beneficial results, for it led to a rectification in 1832, in a sense favourable to Greece, of the frontier drawn by the powers in 1830 (see his Observations on an Eligible Line of Frontier for Greece, London, 1830). Church had, however, surrendered his commission, as a protest against the unfriendly government of Ioannis Kapodistrias, on August 25, 1829. He lived for the rest of his life in Greece, was created general of the army in 1854, and died at Athens on the March 30, 1873. Sir Richard Church married in 1826 Elizabeth Augusta Wilmot-Horton, who survived him till 1878.
- Sir Richard Church, by Stanley Lane Poole (London, 1890)
- Sir Richard Church in Italy and Greece, by EM Church (Edinburgh, 1895) based on family papers (an Italian version, Brigantaggio e societé segrete nelle Fugue, 1817-1828, executed under the direction of Carlo Lacaita, appeared at Florence in 1899).
- The Manuscripts Correspondence and Papers of Sir Richard Church, in 29 vols, now in the British Museum (Add. MSS. 3654336571), contain invaluable material for the history of the War of Greek Independence, including a narrative of the war during Church's tenure of the command, which attempts to vindicate Church's reputation against the strictures of Finlay, Mendelssohn-Bartholdy, and other historians of the war (see Cam. Mod. Hist. x. p. 804).