Thomas Denman, 3rd Baron Denman (16 November 1874 - 24 June 1954) was the fifth Governor-General of Australia.
Denman was born in London as the son of a court clerk, and was educated at Sandhurst, intending a military career. He unexpectedly inherited his title from his great-uncle in 1894. He had little money until 1903, when he married Gertrude Pearson, daughter of a wealthy manufacturer. He was then able to devote his time to politics, and by 1911 he was Liberal whip in the House of Lords. It seems that the Colonial Secretary offered him the post of Governor-General of Australia to get him out of politics.
The Denmans arrived in Sydney in July 1911. They found Andrew Fisher's Labor government firmly in control. As the most politically liberal Governor-General yet appointed, he got on well with the Labor ministers, and his modesty and generosity with his father-in-law's money made him popular with the public.
But Denman found that he had less real political influence than any previous Governor-General. As Australia, along with the other Dominions, achieved political maturity, the Prime Minister communicated directly with his British counterpart, cutting the Colonial Secretary and the Governor-General out of the loop. The appointment of an Australian High Commissioner in London further reduced the Governor-General's diplomatic role.
In June 1913 the Labor government was unexpectedly defeated at the general elections by Joseph Cook's Liberals. But Labor retained control of the Senate, and was determined to frustrate Cook's government at every turn. By early 1914 it was clear that a constitutional crisis was developing.
Denman was in poor health - that he was allergic to Australia's national flower, the wattle, did not help - and his marriage was suffering from his wife's unhappiness at being so far from home. He felt he lacked the strength to deal with the political situation, and in May 1914 he resigned. Back in Britain, he remained loyal to Asquith and the Liberals and so did not hold office again, leading a quiet life until his death in 1954.
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| width="30%" |Preceded by:
The Earl of Dudley
| width="40%" style="text-align: center;" |Governor-General of Australia
1911–1914
| width="30%" |Succeeded by:
Sir Ronald Munro-Ferguson