Pal·mer·ston 
(pämər-stən, päl-), Third Viscount. Title of Henry John Temple. 1784-1865.
(pämər-stən, päl-), Third Viscount. Title of Henry John Temple. 1784-1865. British politician remembered for his efforts to maintain the balance of power in Europe. He served as prime minister from 1855 to 1858 and 1859 to 1865.