John Arthur Hamilton was the son of the land steward at Hazelwood Estate near Sligo town. His father, William, was a native of Scotland, his mother Sara, a Sligo native. He himself had been born in County Mayo. His age was given as twelve in 1911.
Hazelwood Estate had been owned by the Wynne family but Owen Wynne died without a male heir in 1910. His daughter Murial and her husband Philip Dudley Percival then lived there until 1923.
In the 1901 census the Hamilton family was living in Sligo town and the father's occupation was recorded as manager of a salmon fishery.
J.A.W. Hamilton had six poems published in the Sligo Times in 1911. From February to May of 1912 the same newspaper published five of his poems. Some of these poems bore only the poets initials while others gave the writer's full name.
The Sligo Independent on 7 February 1914 carried the news that William Hamilton was leaving Sligo. John Arthur's poetry made no further appearance in Sligo newspapers until April 1915 when a poem encouraging enlistment was published in the Sligo Independent. At that time he was living in Glasgow.