Prime Minister

Foreign policy was the centrepiece of his term in office. Some historians have been highly critical and said that it was ignorant and indifferent to Britain's greatest needs. However, Thomas Goldsmith argues that Addington and Hawkesbury conducted a logical, consistent and eurocentric balance-of-power policy, rooted in rules and assumptions governing their conduct, rather than a chaotic free-for-all approach.^[1]

Addington's domestic reforms doubled the efficiency of the income tax. In foreign affairs, he secured the Treaty of Amiens in 1802. While the treaty's terms were the bare minimum that the British government could accept, Napoleon Bonaparte would not have agreed to any terms more favourable to the British, and the British government had reached a state of financial collapse from war expenditure, the loss of Continental markets for British goods and two successive failed harvests that had led to widespread famine and social unrest, rendering peace a necessity.^{[citation needed]}

By early 1803, Britain's financial and diplomatic positions had recovered sufficiently to allow Addington to declare war on France, when it became clear that the French would not allow a settlement for the defences of Malta that would have been secure enough to fend off a French invasion that appeared imminent.^{[citation needed]}

At the time and ever since, Addington has been criticised for his lacklustre conduct of the war and his defensive posture. However, without allies, Britain's options were limited to defence. He increased the forces, provided a tax base that could finance an enlarged war and seized several French possessions. To gain allies, Addington cultivated better relations with Russia,^[2] Austria, and Prussia, which later culminated in the Third Coalition shortly after he left office. Addington also strengthened British defences against a French invasion through the building of Martello towers on the south coast and the raising of more than 600,000 men at arms.^[3]

Lord President and Lord Privy Seal

Addington remained an important political figure because he had gained a large following of MPs who supported him loyally in the Commons. He was reconciled with Pitt in December 1804, with the help of Lord Hawkesbury as an intermediary. As a result, Pitt arranged for him to join the Cabinet as Lord President of the Council in January 1805 but insisted for Addington to accept a peerage to avoid the inconvenience of them sitting together in the Commons and Addington was created Viscount Sidmouth, of Sidmouth in the County of Devon on 12 January 1805.^[5]

In return for the support of the government by Addington's loyal supporters, Pitt agreed to include Addington's colleague the Earl of Buckinghamshire as Chancellor of the Duchy of Lancaster with a promise to elevate him to the first vacancy of a more senior position in the Cabinet. However, when Melville resigned as First Lord of the Admiralty in July 1805, Pitt broke his promise by having Sir Charles Middleton appointed instead of Buckinghamshire. As a result of the betrayal, Addington and Buckinghamshire resigned and took all of their supporters into opposition. Addington was appointed Lord Privy Seal in 1806 in the Ministry of All the Talents that succeeded Pitt. Later that year he returned to the position of Lord President to 1807. His resignation, in opposition to a limited measure of Catholic Emancipation, which the Cabinet was considering despite the opposition of King George III, precipitated the fall of the Talents Ministry.^{[citation needed]}

Home Secretary

He returned to government again as Lord President in March 1812, and, in June of the same year, became Home Secretary. As Home Secretary, Addington countered revolutionary opposition, being responsible for the temporary suspension of habeas corpus in 1817 and the passage of the Six Acts in 1819. His tenure also saw the Peterloo Massacre of 1819. He left office in 1822, succeeded as Home Secretary by Sir Robert Peel, but Addington remained in the Cabinet as Minister without Portfolio for the next two years, opposing, along with the Duke of Wellington, other members of Cabinet, and King George IV, British recognition of the South American republics. He remained active in the House of Lords for the next few years, making his final speech in opposition to Catholic Emancipation in 1829 and casting his final vote against the Reform Act 1832.