Mary Hughes was the daughter of the Rev. Edward Hughes, Anglican Rector of Norbury, in Staffordshire. He died when she was a child, leaving her mother, Mary, and her two elder sisters, Isabel (1747-1820) and Anne (1752-1824) (who married Howell Hughes at Hanwood on 31 October 1781, and one brother, John (1754-1852), who later became, like his father, an Anglican minister, completing his B.A. at St. John’s College, Cambridge, in 1776 and later serving for many years at Dodderhill, Worcesterhire. After her father’s death, the family settled at Hanwood, near Shrewsbury, Shropshire, where her mother instilled in Mary the virtues of the devotional life and a life of “rigid self-denial,” imbibing a “deep sense of religion” that her niece, Mary Ann Price, described in her obituary of Hughes as “feelings of diffusive benevolence, which in after life formed the distinguishing traits in her character” (Price, “Mrs. Mary Hughes,” 114; Aspland, “Memoir,” 735). 

Though raised a devout Anglican, sometime in the early 1780s, during a long absence by Mary, her mother and sisters left the Anglican church and began attending with a small group of Unitarians meeting in the home of the former Anglican minister at Hanwood, the Rev. Edward Harries (1742-1812), who during Mary’s absence had decided to openly become a Unitarian. Upon her return Hughes was much grieved about the turn of events, but soon after became a believer in the “Divine Unity”  (Aspland, “Memoir,” 735, 736).  After the death of her husband, Howell Hughes, Anne Hughes returned to Hanwood and lived thereafter with her two sisters, assisting Mary in the formation of a Sunday School and in continuing the Unitarian meeting in their own home after the death of Rev. Harries in 1812.  In 1811, Anne was joined by her daughter, Mary Anne Price, and her young granddaughter, also named Mary Anne (Aspland, “Memoir,” 739-40; M. A. Price, “Mrs. Mary Hughes,” 115.). 

In June 1819, Mary, along with her two sisters and niece Mrs. Price (and her daughter), removed to Bristol where they lived as an extended family in Clifton for the next six years (all three sisters would die between 1820 and 1824). During their time in Bristol they attended the ministry of John Rowe (1764-1832) at the Presbyterian (Unitarian) meeting in Lewin’s Mead (Mary and her sisters had known Rowe since his previous ministry at Shrewsbury, near Hanwood, 1787-98) (Price, “Mrs. Mary Hughes,” 115). During her years in Hanwood and Bristol, Hughes was known not only for her religious tracts but also for her philanthropic activities and charitable giving through the work of her local congregation and the Unitarian Association at large. Though having “long been an invalid,” she wrote to Robert Aspland in January 1812, she did not let her physical ailments restrict her desire to write, consistently composing tracts and letters for the Monthly Repository from 1809 through her death on 14 December 1824, in her 69th year (Price, “Mrs. Mary Hughes,” 115).

Robert Aspland felt a need for the distribution of moral and religious tracts from a Unitarian perspective and in 1808 he helped establish the Christian Tract Society [a Unitarian endeavor, not to be confused with the evangelical Religious Tract Society]. Mary Hughes was an early contributor of both money and tracts to the Society. Her first tract was also the Society's first tract, William’s Return, or Good News for Cottagers. The second tract was by Richard Wright and the third by Catherine Cappe. Mary Hughes’ niece, Mrs. M. A. Price, also wrote some of the early tracts. Aspland’s son notes that “At the time when it was established, there were comparatively few publications for the poor that were not disfigured by a sectarian spirit, or by other objectionable qualities. This, happily, is no longer the case; yet it is to be hoped that the sterling excellencies of the Christian Tracts and the increasing demand for such works, will ensure to the Society a succession of supporters as liberal and successful as were its founders” (Aspland, “Memoir,” 359). The original Committee of the Christian Tract Society included Aspland, William Frend (Mary Hays’s former beau and friend of George Dyer), and J. T. Rutt (Hays’s friend and distant relation by marriage which included the family of Henry Crabb Robinson). Mary Hays, however, does not appear to have written any tracts for this Society, though she did write two for the Prudent Man's Society of Bristol. 

Though he had known of her as a writer for some time and even corresponded with her, they did not officially met until the summer of 1813, when Aspland was on a preaching tour of various counties in the Midlands and the West of England (Aspland, “Memoir,” 734). She wrote to him on 23 January 1812 about her life (she had only been introduced to Unitarian culture and the Monthly Repository in 1807), lamenting, with him,

the coldness and worldly-mindedness of many rational believers, a stronger proof of which could not be given than a diminution in the sale of the Repository. To view our Maker as he is, all goodness and benevolence, does not seem to excite a degree of love and gratitude sufficient to animate them to exertion; the base principle of fear appears to have a more powerful influence on the generality of people than the brightest and most glorious hopes and expectation. ‘This,’ Hannah More would triumphantly say, ‘clearly proves the deep corruption of our nature.’ But we shall not be forward to join her in throwing our crimes and follies on our first frail progenitor, or rather in believing that an infinitely just God formed a weak, fallible creature, and to punish his transgression caused all his successors of the human race to be born with hearts ‘desperately wicked’ and inclined to evil continually. You will guess that I have been reading ‘Practical Piety,’ a work which, though much that is good is taught in the course of it, as far as I have gone, leaves a gloomy, disagreeable impression upon my mind, unfavourable to a love of our Creator, or a cheerful performance of the duties he requires from us” (Aspland, “Memoirs,” 737-38).