Valentine Greatrakes was born on 14 February 1628 at the family home at Norrisland, New Affane, County Waterford. His parents were William Greatrakes and Mary Harris, daughter of Sir Edward Harris, 2nd Justice of the Kings Bench in Ireland and Chief Justice of Munster. After the Munster Plantation Valentine's grandfather had settled in County Waterford from Derbyshire. At the outbreak of the Munster Rebellion in 1641, his mother decided to move the family to England to live with her brother Edward in Devon. In 1647 Valentine returned to Ireland: 'I returned to my native country which at that time was in a most miserable and deplorable state, for then it was not as formerly, a National Quarrel, Irish against English, Protestants against Papists, but there were high and strange divisions ...English against English, Irish against Irish, and Protestants and Papists joining hands in one Province against Protestants of another'. He lived at Cappoquin Castle for a year in 'contemplation'.

In 1649 he became lieutenant in the Cromwellian army in the Earl of Orrery's regiment. On leaving the army in 1654 he returned to the family home: 'I betook myself to a Country Life...and got by my industry a livelihood out of the Earth and daily employed many poor people'. He was appointed Clerk of the Peace for Co. Cork and Register of Transplantation. In 1661 he was involved in a noted witchcraft trial in Youghal Co. Cork. Florence Newton of Youghal was accused of 'bewitching' one Mary Langdon. Greatrakes and other officials carried out a series of gruesome tests (lancing her skin and sticking awls into her body) to prove she was a witch.

In 1663 at the age of 34, Valentine "had an impulse or strange persuasion....which did very frequently suggest to me that there was bestowed on me a gift of curing the Kings Evil (a disfiguring skin disease known as Scrofula). Valentine's first patient was a young boy, William Maher of Salterbridge, Cappoquin who suffered from Scrofula. 'I laid my hands on the place affected, and prayed to God for Jesus sake to heal him and within a month ... was perfectly healed, and so continues God be praised'. For three years he concentrated on curing Scrofula. In 1665 he had a further experience leading him to believe that he could cure many other diseases. His fame as a healer spread quickly and he was inundated with people visiting his home. He was forced to move to Youghal 'where great multitudes resorted to me, not only of the inhabitants, but also out of England'. One of these English visitors was John Flamstead (The astronomer?) who travelled from England for a cure for an unspecified illness. He met Greatrakes at his home and described him thus: 'He had a kind of majestical yet affable presence, a lusty body and composed carriage'.

Greatrakes was summoned before the Bishop's Court in Lismore to explain about his activities. He was ordered to cease his healing sessions, but after a few days he decided to ignore their advice. Greatrakes was popularly known as 'The Stroker' because of his method of stroking his patients with his hands.

In 1666 Edward Conway of Ragley Hall in Warwickshire learned about the Irish healer who was creating a sensation with his remarkable cures. Conway's wife Lady Anne had suffered for many years with severe headaches and could not find relief. Lord Conway contacted Michael Boyle, Archbishop of Dublin and asked him to use his influence to persuade Greatrakes to visit Ragley. Greatrakes agreed with reluctance and arrived at Ragley Hall on 27 January 1665. The Conways counted amongst their friends some of the most noted physicians, philosophers, scientists and spiritualists in England. A distinguished group gathered at Ragley to witness Greatrakes attempt to cure Lady Anne Conway. He was unsuccessful with Lady Conway but he was asked to stay at Ragley for a month and is said to have cured many. While there he was invited to Worcester to visit Charles II at Whitehall. He attracted huge crowds in London and Robert Boyle witnessed many of his healing sessions. His supporters and detractors published several pamphlets and ballads concerning his healing. Greatrakes wrote to Lord Conway in May 1666: 'The Virtuosi have been daily with me... and God has been pleased to do wonderful things in their sight. Sir Heneage Finch says that I have made the greatest faction and disturbance between clergy and laymen that anyone has these 1000 years'.

In 1666 Greatrakes published an account of his life and cures titled 'A Brief Account of Mr. Valentine Greatrakes and Divers of the Strange Cures by him lately performed. Written by himself in a letter Addressed to the Honourable Robert Boyle, Esq.,' This publication gives us a valuable insight into Greatrakes life and healing methods. It includes an etching of Greatrakes curing William Maher of Salterbridge.

Greatrakes returned to England for further visits but it is not known when he stopped his healing sessions.

His funeral entry at the Herald's Office, Dublin recorded that he died on 28 November 1682 at Affane, Co. Waterford and was buried in Lismore Church. However, the Rev. Samuel Hayman writing in the 1860's stated that he is buried in the aisle of the old Affane Church near to his father.