Digby, Simon (c.1645–1720), miniature-painter and bishop of Elphin, was born at Kilminchy, Queen's Co. (Laois), youngest son of Essex Digby and his wife Thomasine, daughter of Sir William Gilbert of Kilminchy, Queen's Co. Essex Digby became dean of Cashel in 1661 and bishop of Dromore in 1670. During the commonwealth he was minister of Belfast. Simon Digby entered TCD on 14 May 1661 and received his BA degree three years later. Having taken orders, he was made rector of Dunshaughlin, Co. Meath. In 1668 he became chaplain to the lord lieutenant, James Butler (qv), 1st duke of Ormond. He was appointed prebendary of Lismore on 22 February 1670. In 1677 he was elected dean of Kildare, having already held a prebend in Geashill, Co. Kildare. In December of the same year he was awarded a DD at Oxford. He became bishop of Limerick in March 1678 and was translated to the see of Elphin in 1691.
He was also a noted amateur painter of portrait miniatures in watercolour, though it is not known where he received his training. Bishop Downes, writing in April 1720 to Archbishop Wake of Canterbury, described Digby as ‘a great master of painting in little watercolours and by that quality recommended himself to men in power and ladies, and so was early made a bishop’ (RSAI Jn., xii (1873), 253). His sitters included Archbishop Narcissus Marsh (qv), Lord Capel, and Henry, Lord Sidney. His portrait (painted in 1692 in watercolour on ivory) of John Tillotson, archbishop of Canterbury, is in the NGI. A miniature of John Hough, bishop of Worcester, is in the collection of the National Portrait Gallery, London. Digby's own portrait by an unidentified artist is in the collection of his descendants at Sherborne Castle, Dorset, as are a number of other examples of his work. One work in pastel by him is known, a portrait of the 1st duke of Ormond, the style of which has been compared with that of the English painter Edmund Ashfield (Watercolours of Ireland, 26).
He married (date unknown) Elizabeth, daughter of Warner Westenra; they had eight sons and eight daughters. His second daughter, Lettice, married the Rev. William Brooke of Rantavan, Co. Cavan, rector of Killinkere and Mullagh in the same county. He died on 7 April 1720 at his home in Lacken, Co. Roscommon, and was buried at the church of Tosara (Mount Talbot) on 20 April.