<Tr> <Th_colspan="11"> Whig (17) Tory (11) Conservative (17) Peelite (1) Liberal (7) Labour (6) National Labour (1) </Th> </Tr> <Tr> <Th_colspan="2"> Portrait </Th> <Th> Prime Minister (Birth--Death) </Th> <Th_colspan="3"> Term of office & mandate Duration in years and days </Th> <Th> Ministerial portfolios held as Prime Minister </Th> <Th> Party </Th> <Th> Ministry </Th> <Th> Monarch (Reign) </Th> <Th> Ref . </Th> </Tr> <Tr> <Td> </Td> <Td> </Td> <Td> The Right Honourable Robert Walpole 1st Earl of Orford KG KB PC MP for King's Lynn (1676--1745) </Td> <Td> 4 April 1721 </Td> <Td> 11 February 1742 </Td> <Td> 1722 </Td> <Th> <Ul> <Li> First Lord of the Treasury </Li> <Li> Chancellor of the Exchequer </Li> <Li> Leader of the House of Commons </Li> </Ul> </Th> <Td> Whig </Td> <Td> Walpole--Townshend </Td> <Th> George I (1714--1727) </Th> <Td> </Td> </Tr> <Ul> <Li> First Lord of the Treasury </Li> <Li> Chancellor of the Exchequer </Li> <Li> Leader of the House of Commons </Li> </Ul>

When did england elect its first prime minister
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