John Davidson (11 April 1857 – 23 March 1909) was a Scottish poet, playwright and novelist, best known for his ballads. He also did translations from French. In 1909, financial difficulties, as well as physical and mental health problems, led to his suicide.

He was born at Barrhead, East Renfrewshire as the son of Alexander Davidson, an Evangelical Union minister and Helen née Crocket of Elgin. His strict Protestant upbringing deeply influenced the type of man and writer he would become. Harold Herbert Williams writes: "Like Carlyle he was a protagonist of the actual, for in boyhood he had been trained in the strictest sect of the Calvinists, and like Carlyle he spent half his life buffeting the universe as a Calvinist without dogma."

His family removed to Greenock in 1862 where he was educated at Highlanders' Academy there and entered the chemical laboratory of Walker's Sugarhouse refinery in his 13th year, returning after one year to school as a pupil teacher. Davidson also briefly worked in the Public Analysts' Office, from 1870 to 1871. In these employments he developed an interest in science which became an important characteristic of his poetry. In 1872 he returned for four years to the Highlanders' Academy as a pupil-teacher, and, after a year at University of Edinburgh (1876–77), received in 1877 his first scholastic employment at Alexander's Charity, Glasgow. During the next six years he held positions in the following schools: Perth Academy (1878–81), Kelvinside Academy, Glasgow (1881–82), and Hutchinson's Charity, Paisley (1883–84). He varied his career by spending a year as clerk in a Glasgow thread firm (1884–85), and subsequently taught in Morrison's Academy, Crieff (1885–88), and in a private school at Greenock (1888–89).

Having taken to literature, he went in 1889 to London where he frequented 'Ye Olde Cheshire Cheese' and joined the 'Rhymers' Club'. Davidson's first published work was Bruce, a chronicle play in the Elizabethan manner, which appeared with a Glasgow imprint in 1886. Four other plays, Smith, a Tragic Farce (1888), An Unhistorical Pastoral (1889), Aromantic Farce (1889), and the brilliant pantomimic Scaramouch in Naxos (1889) were also published while he was in Scotland.

Besides writing for the Speaker, the Glasgow Herald, and other papers, he produced several novels and tales, of which the best was Perfervid (1890). But these prose works were written for a livelihood.

Davidson's true medium was verse. In a Music Hall and other Poems (1891) suggested what Fleet Street Eclogues (1893) proved, that Davidson possessed a genuine and distinctive poetic gift. The late nineteenth century English novelist George Gissing read both these volumes in one day in 1893 at the British Museum Library. Yeats had words of praise for In a Music Hall. He called it, "An example of a new writer seeking out 'new subject matter, new emotions'". Yeats wrote of his emotional dispute with Davidson in Autobiographies (1955). The second collection established his reputation among the discerning few. His early plays were republished in one volume in 1894, and henceforward he turned his attention more and more completely to verse. A volume of vigorous Ballads and Songs (1894), his most popular work, which Davidson sent a copy of to George Gissing, who wrote that it "gave me thoughts", was followed in turn by a second series of Fleet Street Eclogues (1896) and by New Ballads (1897) and The Last Ballad (1899).

For a time he abandoned lyric for the drama, writing several original plays.

Finally Davidson engaged on a series of "Testaments", in which he gave definite expression to his philosophy. These volumes were entitled The Testament of a Vivisector (1901),The Testament of a Man Forbid (1901), The Testament of an Empire Builder (1902), and The Testament of John Davidson (1908). Though he disclaimed the title of philosopher, he expounded an original philosophy which was at once materialistic and aristocratic. The cosmic process, as interpreted by evolution, was for him a fruitful source of inspiration.