MMS 's mother was born Martha Sherwood and was heiress to £10,000 from her father, a merchant in Coventry and London. Shy, unattractive, marked by smallpox, with no interest in clothes or appearance, she was her husband's second choice after the death of the beautiful young woman (her close friend) whom he had planned to marry. She brought up her children with rigour. Later she gave MMS a prayer-book which had been owned by women in the family for five generations. She died on 20 March 1817, after Mary Martha had returned from India.

MS seems to waver about how to conclude her story. Statira's disgrace is salved when the count's sister (a nun) tells him the story of a woman, Idela de Toggenburg, who had the fortitude to leave her unworthy husband and enter a convent, although she loved him. This tale causes Harton to entertain, for the first time, the possibility of his wife's innocence. But Showes chooses after all not to give the novel a happy ending on Statira's vindication. Instead Statira, still not received by her husband, re-appears in the story incognita, in the person of Madame Laborde, a perfect governess for her own children. When the children fall ill with smallpox she nurses them safely through it—only to die of the dread disease herself, leaving her husband to the poignancy of his regrets, for the loss of her, whose worth he did not know how to estimate when living.

A combined French and Spanish fleet, massed in the English Channel for invasion of southern England, retired in disarray after smallpox broke out on one of the ships and spread rapidly.

In addition to writing enormously, SSW worked at running more than one school. She reported in 1819 (the year following her first application for help from the Royal Literary Fund) that she had started a day-school which failed, and was now appointed to the Free School at Braywick near Maidenhead. For this job, which was to lift her out of the evils of poverty and the precarious misery of authorship, she urgently needed to supply herself with decent clothes. She quickly lost the position, however, when her thirteen-year-old daughter got smallpox (presumably because SSW needed to stay at home to nurse her). Very soon afterwards she was offered the job of mistress of a school at Bray in Berkshire (with a reference from the current headmistress at Whitechapel). This appointment again brought an urgent need for respectable clothes, which this time had to be redeemed from pawn. But SSW had to resign the position after nine months because she had developed cancer.

In her poems she mentions her early friendship and admiration for Richard Valpy , polymath headmaster of Reading School , and Henry Moyes , a scientist and lecturer of Scottish origin (whose intellectual attainments were the more remarkable since he was totally blind from a childhood attack of smallpox). Moyes died in 1807.

After some years of investigating the protection given by cowpox against smallpox, Edward Jenner carried out his first, experimental cowpox injection of a healthy young boy. His subject showed no reaction when later inoculated with smallpox.

MS contracted smallpox while visiting Paris; but she survived.

Politician, agriculturalist, and statistician Sir John Sinclair of Ulbster , first baronet (1754-1835), used to joke that he had six-and-thirty feet of daughters. This was a way of putting the the fact that all of his six daughters, including Catherine, were about six feet tall. In fact, the pathway outside the Sinclair home in Edinburgh, paved with enormous slabs of stone brought from the family home in Caithness, was colloquially called the Giants' Causeway. Sir John, immortalized in a Raeburn portrait, was well known for the pioneering work which resulted in The Statistical Account of Scotland, published in 1791-9. As Catherine Sinclair's great-niece Lucy Walford recollected, he was also known as a wonderful person, and many of his children, including Catherine, inherited his appealing temperament. However, as an amateur man of science Sir John insisted on carrying out himself the inoculation of several of his daughters for smallpox, only to be dismayed at the result—for some were marked for life—he urged upon the doctor to skin their faces, and was furious at a refusal.

The smallpox vaccination method established by Edward Jenner was coming into use around the world; in England about 100,000 people had been vaccinated, and the annual smallpox death rate (which had averaged about 3,000 per million inhabitants) sank to about 1,173 in 1802 and 622 in 1804.

The Royal Philanthropic Expedition set sail in three ships from La Coruna, to carry the practice of vaccination against smallpox to Spanish possessions in South America and Spanish outposts in China (Canton) and Macao).

MG contracted smallpox, but survived.

An epidemic of smallpox in Norwich led doctors to strengthen their demand for compulsory vaccination.

As an infant, the future queen was breast-fed, and vaccinated against smallpox.

Helen Neale, the daughter of an Anglican clergyman, first hears of Father Phim as someone after whom her brother Hilary, as an irritating joke, insists on calling her: fat Father Phelemy Phim Philip M'Quirk. But when she is sent from her urban English home to convalesce at her grandfather's estate in Ireland after having had smallpox, Father Phim (the local Roman Catholic priest) becomes her best friend, while Helen herself becomes a friend and then a defender of her grandfather's tenants, and the estate bailiff, Mr O'Rhea, becomes the object of her hatred. The story is set in the time of the Great Famine, and the hardships of the tenants' lives are a shock to Helen.