It was named after Henry John Temple, 3rd Viscount Palmerston who was a British Prime Minister.

The 3rd Viscount of Palmerston, Henry John Temple, was the Prime Minister of the United Kingdom from 1855 to 1858.

Henry John Temple.

Henry John Temple Palmerston has written:

'Lord Palmerston on the treaty of Washington' -- subject(s): Great Britain. 1842 Aug. 9., Great Britain, Treaty of Washington

Fort Apache John Wayne had top billing, then Henry Fonda, then Shirley Temple, and Pedro Armendariz. So I would say it was actually a John Wayne film with Henry Fonda in it.