Mary (Maria) Brown Austin, wife of Moses Austin and mother of Stephen F. Austin and Emily Margaret Austin Bryan Perry, daughter of Abia and Margaret (Sharp) Brown, was born at Sharpsborough Furnace, New Jersey, on New Year's Day, 1768, one of eight and the oldest living child. Her father had served as a deputy in the provincial congresses of 1775 and 1776 and amassed holdings in real estate in connection with iron mining and smelting. After Mary's mother died in 1780, her father asked the wealthy Philadelphia merchant Benjamin Fuller, connected by marriage to the Sharp family, to board Mary and one of her sisters. After a courtship of no more than two years, Mary married Moses Austin in 1785 and moved to Richmond, Virginia, where Moses established and prospered in a branch of a mercantile partnership he shared with his brother. In Richmond Mary managed a household of up to half a dozen slaves in the most imposing residential structure there. She gave birth to Anna Maria (1787) and Eliza Fuller (1790), each of whom died within months of birth. Mary moved with Moses in 1792 to the frontier at the Lead Mines, soon renamed Austinville, in modern Wythe County, Virginia, where she gave birth to Stephen Fuller (1793), later known as the "Father of Texas," and Emily Margaret (1795). When Austin's business in Virginia began to fail, he moved his family in 1798 to Ste. Genevieve, then to Potosi, the first Anglo-American settlement west of and back from the Mississippi River, in Spanish Upper Louisiana (modern Missouri). Moses built a mansion in the Southern style, over which Mary presided, and where in 1803 she bore their fifth child, James Elijah Brown Austin.
Maria, as her family came to call her, was a steady, capable woman in whom her husband confided concerning his business affairs. During his extended business trips, she managed both the household and her husband's business affairs at home. Always frugal, she demonstrated a strong capability for handling money and managing finances. Life on the Missouri frontier was hard on her physically. She lost weight and by 1811 endured nearly constant pain. A change of climate, she and her husband decided, might do her good. Moreover, a trip to the East would give her the joy of renewing acquaintances with kin, none of whom, save one sister, she had seen since before she left Virginia thirteen years earlier. Moses and Maria agreed, too, that she should take their two youngest children, seven-year-old Brown so that he could meet his relatives, and sixteen-year-old Emily so that she could enter a good Eastern school to finish her education. Maria and the children were escorted by a brother-in-law of her husband, whose business shortcomings aggravated her, but whose unannounced abandonment of them on the East Coast left her free to manage her own affairs. Maria was happy in the East; she begged her husband to abandon Missouri and establish a business there. Upon declaration of the War of 1812 she curtailed her social life to conserve on the cost of living, but sorrow and loneliness made her life miserable. She returned to Missouri in the summer of 1813, in time for Emily's marriage to James Bryan. The next year Emily bore a son, but fell so ill that Maria had to care for him. When the baby died a month later, Maria was devastated. Thereafter, her health deteriorated steadily. By 1817 rheumatism had destroyed her ability to write. By 1817 financial troubles had bereft Maria and Moses of their home of eighteen years in Potosi. They moved to Herculaneum, a town Moses had founded ten years earlier on the Mississippi. In 1820 Maria's anxiety increased, both on account of the death of close friends, who, without having forewarned her, left their son to Maria's care, and on account of Austin's deteriorated financial condition, which led him to declare bankruptcy in March. In May 1820, against Maria's wishes, Moses left home for Arkansas. He subsequently sought permission to establish an Anglo-American colony in Spanish Texas. When she saw Moses again ten months later in March 1821, Maria found him terribly debilitated and begged him to rest. He refused. On June 8, 1821, two days before Moses died, Maria, hoping desperately for her husband's recovery, wrote one of the most widely known letters in Texas history in which she told their son, Stephen Fuller, of Moses' wish for him to pursue the Texas colonization venture.
With more liabilities than assets in her husband's estate, the widowed Maria at fifty-three had to support herself, which she did in part by making bonnets for sale. She and Emily, whose husband died in 1822, hoped to recover the home Moses had built in Potosi, but it was not to be. Living with Emily in her last years, Maria focused on religion and her grandchildren. She died at Emily's home on Hazel Run, twenty miles east-southeast of Potosi, on January 8, 1824. Maria was buried beside her husband in the private graveyard on the Bryan property. She had wanted Austin's body moved to a public cemetery. Before Emily and her second husband moved to Texas in 1831, they had the remains of both Maria and Moses reinterred in a public cemetery in Potosi on land once owned by them.