Manning was born in Wagga Wagga, New South Wales, to pastoralists Frederick and Jane Belle Manning. He was educated in public schools in Wagga and Yass before purchasing grazing land in Narrabri and West Wyalong; he married Florence Hogarth in 1899, a union which produced no children. He became a vocal proponent for the rights of farmers, serving as president of the Australian Meat Council and on the boards of the Farmers and Settlers' Association and the Graziers' Association.
Member of parliament
At the 1917 state election, Manning won the seat of Albury for the Nationalist Party. Defeated at the 1920 state election, Manning remained involved in the Nationalist Party and rural affairs and was chosen as the Nationalist candidate for the Division of Macquarie at the 1922 federal election. Manning was victorious, narrowly defeating sitting Labor representative Samuel Nicholls by less than 100 votes after preferences from an independent were distributed. Manning faced controversy during his first term in federal parliament when it was revealed in 1924 that he and fellow parliamentarian farmer William Killen had signed cheques on behalf of the government to the Australian meat industry. This was considered by some to be in breach of section 44 of the Australian constitution, whereby members of parliament were banned from deriving a benefit from government actions. Following a lively parliamentary debate, a motion that Manning and Killen were in breach of section 44 was defeated. Despite the controversy, Manning retained his seat at the 1925 election, defeating Labor candidate and future prime minister Ben Chifley. In 1926, Manning was a member of the Australian delegation to the League of NationsGeneral Assembly, discussing, amongst other issues, Australia's administration of the former German New Guinea. Manning was opposed by Chifley again in 1928, and narrowly lost following a Labor campaign that painted Manning a friend of Asian immigrants. Chifley argued that he would help keep Australia white and while Manning used his campaign speeches to deny that he was in favour of Asian immigration, the electorate was in no mood for someone they considered soft on immigration.
Later life
Out of parliament, Manning remained on the executive of the Nationalist Party and stood as the official Nationalist Party candidate for the suburban Sydney federal Division of Wentworth at the 1929 election, following the expulsion of the sitting member Walter Marks from the party. Manning lost and returned to his life as a gentleman grazier while remaining involved in farming and political issues, including a stint as a United Australia Party councillor from 1933 to 1935. He died in Sydney.
