Henry John Temple, 3rd Viscount Palmerston, (20 October 1784 – 18 October 1865) was a British statesman who served twice as Prime Minister in the mid-19th century. Popularly nicknamed "Pam" and "The Mongoose", he was in government office almost continuously from 1807 until his death in 1865, beginning his parliamentary career as a Tory, switching to the Whigs in 1830, and concluding it as the first Prime Minister of the newly-formed Liberal Party from 1859.