on 4 July 1853, Dundas was appointed Third Naval Lord in the Aberdeen ministry in January 1853 and then Second Naval Lord in the same ministry in June 1854. He was appointed to the command of the Baltic Fleet in the Baltic Sea, hoisting his flag in the first-rate HMS Duke of Wellington, in succession to James Dundas in February 1855. Dundas led the naval support during the latter stages of the Crimean War enforcing a strict blockade in the Baltic. Dundas was hesitant but the French admiral Charles Penaud persuaded him to attack the Russian fleet in the harbour of Sweaborg on 9–10 August 1855. The British provided most of the attacking force. Much of the bombardment was done with smaller vessels that the shore batteries found hard to hit. Six Russians ships of the line and 17 smaller warships were destroyed, and the Russians suffered 2,000 casualties. The allies suffered one death, 15 wounded, and damage to only one British sloop. Dundas was advanced to Knight Commander of the Order of the Bath on 5 February 1856 and became Second-in-command of the Mediterranean Fleet, hoisting his flag in HMS Duke of Wellington, in April 1856. He was also appointed a Grand Officer of the French Legion of Honour on 2 August 1856. Dundas was appointed Second Naval Lord in the First Palmerston ministry in April 1857 and then First Naval Lord in the same ministry in November 1857. Promoted to vice-admiral on 24 February 1858, Dundas stepped down to be Second Naval Lord in the Second Derby ministry in March 1858. He stepped up again to become First Naval Lord in the Second Palmerston ministry in June 1859 remaining in office until his death. He died, unmarried, of a heart attack at Spring Gardens in London on 3 June 1861. Later that day, the Prime-Minister (Viscount Palmerston) described Vice Admiral Dundas as: "a most distinguished officer, who was for forty-five years in the service of his country, and who equally distinguished himself in every sphere in which he was called upon to act. He was eminent for the good discipline and order of the ships which he commanded, he was distinguished by the gallantry and good judgment with which he conducted every naval operation in which he was engaged, he was most valuable as a public servant in the direction of naval affairs at the Admiralty. Whether at