sixth-rate HMS Tweed and took part in the Battle of Luchana, an operation to defend the Port of Bilbao on the north coast of Spain, in December 1836 during the First Carlist War. As a result of this he was awarded the knight's cross of the Order of Charles III for his support for the liberal forces of Maria Christina, the Regent of Spain at the time of the minority of Isabella II, who had faced a revolt by Carlos, Count of Molina. Promoted to captain on 10 January 1837, Maitland became commanding officer of the third-rate HMS Wellesley, flagship of Rear Admiral Frederick Maitland serving as Commander-in-Chief of the East Indies and China Station, in June 1837. He saw action off the Persian Gulf in 1839 and then, following the death of Frederick Maitland in November 1839, served under Commodore James Bremer at the Capture of Chusan in July 1840, at the Second Battle of Chuenpi in January 1841 and at the Battle of the Bogue in February 1841 during the First Opium War. He also commanded the 1st naval battalion during the Battle of Canton in May 1841 for which he was appointed a Commander of the Order of the Bath on 29 June 1841. He remained on the station and, after taking part in the Battle of Amoy in August 1841, fought at some of the later battles under Rear Admiral Sir William Parker including the Capture of Chusan in October 1841, the Battle of Ningpo in March 1842, the Battle of Woosung in June 1842 and the Battle of Chinkiang in July 1842 which ultimately led to the Treaty of Nanking ending the war in August 1842. Maitland went on to be commanding officer of the third-rate HMS America off the coast of Portugal in November 1846, commanding officer of the first-rate HMS San Josef, flagship of Admiral Sir William Gage serving as Commander-in-Chief, Plymouth, in April 1848 and commanding officer of the second-rate HMS Impregnable, Gage's new flagship, in January 1849. After that he became commanding officer of the second-rate HMS Agamemnon in the Channel Squadron in September 1852, commanding officer of the first-rate HMS Victory, flagship of Admiral Sir Thomas Cochrane serving as Commander-in-Chief, Portsmouth, in December 1853 and commanding officer of the Gunnery School HMS Excellent at Portsmouth in January 1854. Senior command Promoted to rear-admiral on 18 June 1857, Maitland gave evidence