Nelson was from Skelton, New York He was nearing 40 when he left for Douai in 1573 for training as a priest. He was ordained at Binche in the County of Hainaut by Monsignor Louis de Berlaymont, Archbishop of Cambrai, on 11 June 1576.
The next November, he left for his mission, which appears to have been in London.
He was arrested on 1 December 1578, "late in the evening as he was saying the Nocturne of the Matins for the next day following", and was put into Newgate Prison as a suspected Papist. When interrogated about a week later, he refused to take the oath recognizing the Queen"s supremacy in spiritual matters, and was induced by the commissioners to declare the Queen a schismatic.
Under the Legislation of 1571, this was high treason and was punishable by death. He was condemned to death on 1 February 1578, and was confined after the trial in an underground dungeon in the Tower of London, the Pit of the Tower.
While in prison he subsisted on bread and water and was able to say Massachusetts
When asked to beg pardon of the Queen, he responded, "I will ask no pardon of her, for I have never offended her." He then asked any Catholics in the crowd to pray with him as he recited several common prayers in Latin.
He was hanged and cut down alive, then quartered. His last words were, reportedly, "I forgive the queen and all the authors of my death". He was beatified on 29 December 1886 by Pope Leo XIII.