John Russell, 1st Earl Russell, KG, GCMG, PC, FRS (18 August 1792 – 28 May 1878), known by his courtesy title Lord John Russell before 1861, was a leading Whig and Liberal politician who served as Prime Minister of the United Kingdom on two occasions during the early Victorian era.

Scion of one of the most powerful aristocratic families, his great achievements, wrote A. J. P. Taylor, were based on his persistent battles in Parliament over the years on behalf of the expansion of liberty; after each loss he tried again and again, until finally, his efforts were largely successful. E. L. Woodward, however, argued that he was too much the abstract theorist:

He was more concerned with the removal of obstacles to civil liberty than with the creation of a more reasonable and civilized society. His political theory centred in the revolution of 1688, and in the clique of aristocratic families to whom the country owed loyalty in return for something like the charte octroyée of the reform bill.[1]

Nevertheless, Russell led his Whig party into support for reform; he was the principal architect of the great Reform Act of 1832.

As Prime Minister he was less successful. He headed a government that failed to deal with the Irish Famine, a disaster which saw the loss of a quarter of Ireland's population. It has been said that his ministry of 1846 to 1852 was the ruin of the Whig party: it never composed a Government again, and his ministry of 1865 to 1866 was very nearly the ruin of the Liberal Party also