1769 – He was born on the 18th of June in Dublin.
1794 – He married Emily Anne Hobart, a beautiful if slightly eccentric woman to whom he remained devotedly attached throughout their long and childless marriage.
1798 – In March, he served as acting chief secretary to his relative Earl Camden, then lord lieutenant of Ireland.
– In November, he was formally appointed to that office by Camden’s successor, Lord Cornwallis.
1801 – Castlereagh continued to advise Henry Addington’s ministry on Irish questions.
1802 – In July, he was appointed president of the Board of Control responsible for Indian affairs.
1805 – His first important task, the dispatch of a British expeditionary force to Hanover, was rendered ineffectual by Napoleon’s victory at Austerlitz but the move convinced Castlereagh of the strategic value of the British Army in continental warfare.
1806 – In January, he left office and became the chief opposition spokesman on foreign and military affairs.
1807 – He returned to the War Department in the Duke of Portland’s ministry and showed his determination to engage in major warfare against a continent now completely dominated by Napoleon.
1809 – Castlereagh was influential in securing the command for Sir Arthur Wellesley (later duke of Wellington).
1812 – He rejoined the government as secretary for foreign affairs, and after Prime Minister Perceval’s assassination in May he became leader of the House of Commons.
1814 – He secured acceptance in principle of his plans for a peace settlement under the control of the great powers.
1820 – He refused to treat their meeting at Troppau in October as a full European congress, and after the Congress of Laibach, he openly repudiated the Troppau principle of intervention and coercion.
1822 – He died on the 22nd of August in London.