John Henry Nicholson (12 June 1838 – 30 June 1923) was an Australian teacher and writer.
Nicholson was the son of John Nicholson, an oriental scholar of distinction, and the first English friend of Ludwig Leichhardt. Nicholson was born at Lyme Regis, Dorset, England, was educated at Croft House academy, and emigrated to New South Wales in 1854. He went to Queensland in 1859, opened a private school at Toowoomba in 1860, and in 1863 had a school at Warwick. He joined the Queensland education department in May 1865 as an assistant teacher. He resigned in 1868 in order to visit England, rejoined the department in June 1869, and later had charge of several country state schools.
Between 1867 and in 1878 he published three little books of miscellaneous prose and verse, facetious and satirical in character and not of much merit. So far back as 1856, however, he had begun to brood over the idea of writing an allegorical history of a man's life on the earth, and in 1873 he wrote the early chapters of The Adventures of Halek, which was published in London in 1882. He resigned from the education department in April 1885 but rejoined some years later and was head teacher of the state school at Cambooya from September 1893 to the end of 1894 when he finally gave up teaching. He was then appointed registrar of births, marriages and deaths at Nundah near Brisbane. A second edition of Halek was published in 1896 at Brisbane, and a third appeared in 1904. In the same year Almoni, described as a companion volume to Halek, was also published at Brisbane.
When Nicholson was approaching 70 years of age a Swedish literary woman, who had been attracted by his work, came to Australia from California and married him. In his later years Nicholson, who had always been inclined to be erratic, would sometimes voluntarily go to the mental hospital at Goodna until he felt fit to face the world again. He died at Brisbane on 30 June 1923 at the age of 85. His wife survived him. There were no children.