On February 13, 1827, Maitland was appointed to the _Wellesley_, 74. In December 1826, Mr Canning, in response to an appeal from the Portuguese Regency, had sent English troops to Lisbon to protect the Government of Portugal against the threatened attack of Spain. Maitland was ordered to Lisbon, and the _Wellesley_ spent the autumn and winter of 1827 in the Tagus. After a spring cruise up the Mediterranean, she returned to England in May 1828. On June 26 she again sailed for the Mediterranean, carrying the flag of Admiral Sir Pulteney Malcolm, who was then going out to succeed Sir Edward Codrington in command of the Mediterranean station. On August 24 she joined the squadron under Codrington at Navarino. Maitland remained in Greek waters for the next two years. The tragic drama of the Greek Revolution, after seven years of horrors, had now reached its final act. By the Treaty of London, in July 1827, England, Russia, and France had undertaken to put an end to the conflict in the East, and to establish the autonomy of Greece. In the following October the battle of Navarino had been fought, and the Turkish fleet destroyed. Ibrahim Pasha still held the fortresses of the Morea, which he was shortly to evacuate under the pressure of a French army corps. In April 1828 war had broken out between Turkey and Russia. Desultory fighting was still going on in Crete, which had been utterly devastated by years of barbarous warfare. In October the _Wellesley_ went to Suda Bay, and most of the winter was spent by Maitland on the coast of Crete, endeavouring to bring about an armistice, and superintending the blockade which the Powers had established in order to prevent military supplies from reaching the Turks in the island. The blockade was raised early in 1829; and during the following months Maitland visited nearly every point of interest on the Greek coast and in the Greek islands, as well as Sicily, the coast of Asia Minor, and Constantinople. Like most Englishmen who have served in the Levant, he developed a considerable respect for the Turk, and a quite unbounded contempt for the Greek. After the armistice negotiations in Crete he writes: "I found the conduct of the Turkish chiefs throughout manly, straightforward, and sincere, while that of their opponents was very much the reverse;" and in another place he writes of the Greeks that "a more perfidious, ferocious, and cruel race does not exist." Needless to say he did not think much of "our pretty Greek Committee." In the summer of 1830 the _Wellesley_ returned to England. Maitland attained his flag on July 22, 1830. At the reconstruction of the Order of the Bath in 1815 he had been made a C.B.; on November 17, 1830, he was advanced to be a K.C.B. In 1835 he received the Greek Order of the Redeemer.