William Allingham, March 19, 1824 or 1828 - November 18, 1889 was an Irish man of letters and poet.
He was born at Ballyshannon, Donegal, and was the son of the manager of a local bank. He obtained a post in the custom-house of his native town and held several similar posts in Ireland and England until 1870, when he had retired from the service, and became sub-editor of Fraser's Magazine, which he edited from 1874 to 1879, in succession to James Froude.

He had published a volume of Poems in 1850, followed by Day and Night Songs, a volume containing many charming lyrics, in 1855. Allingham was on terms of close friendship with DG Rossetti, who contributed to the illustration of the Songs. His Letters to Allingham (1854-1870) were edited by Dr Birkbeck Hill in 1897. Lawrence Bloomfield, a narrative poem illustrative of Irish social questions, appeared in 1864.

Allingham married in 1874 Helen Paterson, known under her married name as a water-colour painter. He died at Hampstead.

Though working on an unostentatious scale, Allingham produced much excellent lyrical and descriptive poetry, and the best of his pieces are thoroughly national in spirit and local colouring.