Sir Frederick Lloyd Dumas (15 July 1891 – 24 June 1973), generally known as "Lloyd Dumas" or "F. Lloyd Dumas", was a journalist and politically influential newspaperman in Victoria and South Australia.
Dumas was born in Mount Barker, South Australia, the fourth child and youngest of three sons of Amelia Dumas, née Paltridge, (died 1 November 1938) and Charles M. R. Dumas (1851–1935), who founded the Mount Barker Courier. A grandmother was a sister of Mount Barker pioneer John Dunn and his grandfather, Victor Dumas, ran a highly praised private school in Mount Barker. Any family connection with the great French novelist Alexandre Dumas is as yet conjectural.
He was educated at Mount Barker and Victor Harbor and in 1904 won a scholarship to the Teachers' College. He quit his studies in late 1906 or early 1907 to work for the Adelaide Advertiser and in mid-1910 helped out as interim Murray Bridge correspondent for his father's newspaper. In 1911 he was one of the founders of the South Australian branch of the Australian Journalists' Association. In 1914 he left for Victoria.
Around 1915 he accepted a position on the literary staff of the Melbourne Argus, and worked as a Federal roundsman. He publicly supported the pro-conscription stance of Prime Minister Hughes and was chosen by Hughes to manage the "pro" campaign for the second conscription referendum. In 1918 Dumas accompanied him and Minister for the Navy Cook to the Imperial Conference in England.