They returned to London in April 1721, when Montagu requested that her daughter Mary, who was four, be inoculated. Maitland reluctantly agreed if there were other witnesses present, so three physicians from the Royal College of Physicians were there for the procedure, the first professional inoculation in England. One of the witnesses, James Keith, was so pleased by the success that he had Maitland inoculate his six-year-old son; Keith's other children had all died of smallpox. The Montague family promoted inoculation in England, calling it a "useful invention".
In 1716 Sloane was created a baronet, making him the first medical practitioner to receive a hereditary title. In 1719 he became president of the Royal College of Physicians, holding the office for sixteen years. In 1722 he was appointed physician-general to the army, and in 1727 first physician to George II.
Sir Hans Sloane, 1st Baronet (16 April 1660 – 11 January 1753), was an Irish physician, naturalist and collector noted for bequeathing his collection of 71,000 items to the British nation, thus providing the foundation of the British Museum, the British Library and the Natural History Museum, London. He was elected to the Royal Society at the age of 24. Sloane traveled to the Caribbean in 1687 and documented his travels and findings with extensive publishings years later. Sloane was a renowned medical doctor among the aristocracy and was elected to the Royal College of Physicians by age 27. He is credited with creating drinking chocolate.
The practice was introduced to England by Lady Mary Wortley Montagu. Lady Montagu's husband, Edward Wortley Montagu, served as the British ambassador to the Ottoman Empire from 1716 to 1718. She witnessed firsthand the Turkish use of inoculation in Istanbul, and was greatly impressed: she had lost a brother to smallpox and bore facial scars from the disease herself. When a smallpox epidemic threatened England in 1721, she called on her physician, Charles Maitland, to inoculate her daughter. She invited friends to see her daughter, including Sir Hans Sloane, the King's physician. Sufficient interest arose that Maitland gained permission to test inoculation at Newgate Prison in exchange for their freedom on six prisoners due to be hanged, an experiment which was witnessed by a number of notable doctors. All survived, and in 1722 the Prince of Wales' daughters received inoculations.
Lady Bute was born in 1718, the only daughter of Sir Edward Wortley Montagu and Lady Mary Pierrepont, the daughter of the Evelyn Pierrepont, 1st Duke of Kingston-upon-Hull. She was born during her father's tenure as ambassador to Ottoman Empire, which her mother wrote about in her Letters from Turkey.
In 1716, Edward Wortley Montagu was appointed Ambassador at Constantinople. In August 1716, Lady Mary accompanied him to Vienna, and thence to Adrianople and Constantinople. He was recalled in 1717, but they remained at Constantinople until 1718. While away from England, the Wortley Montagu's had a daughter on 19 January 1718, who would grow up to be Mary, Countess of Bute. After an unsuccessful delegation between Austria and Turkey/Ottoman Empire, they set sail for England via the Mediterranean, and reached London on 2 October 1718.
In December 1715, Lady Mary contracted smallpox. She survived, but while she was ill someone circulated the satirical "court eclogues" she had been writing. One of the poems was read as an attack on Caroline, Princess of Wales, in spite of the fact that the "attack" was voiced by a character who was herself heavily satirised.
On 22 August 1705, Caroline arrived in Hanover for her wedding to George Augustus; they were married that evening in the palace chapel at Herrenhausen. By May of the following year, Caroline was pregnant, and her first child Prince Frederick was born on 20 January 1707. A few months after the birth, in July, Caroline fell seriously ill with smallpox followed by pneumonia. Her baby was kept away from her, but George Augustus remained at her side devotedly, and caught and survived the infection himself. Over the next seven years, Caroline had three more children, Anne, Amelia, and Caroline, all of whom were born in Hanover.
Caroline was born on 1 March 1683 at Ansbach, the daughter of John Frederick, Margrave of Brandenburg-Ansbach, and his second wife, Princess Eleonore Erdmuthe of Saxe-Eisenach. Her father was the ruler of one of the smallest German states; he died of smallpox at the age of 32, when Caroline was three years old. Caroline and her only full sibling, her younger brother Margrave William Frederick, left Ansbach with their mother, who returned to her native Eisenach. In 1692, Caroline's widowed mother was pushed into an unhappy marriage with the Elector of Saxony, and she and her two children moved to the Saxon court at Dresden. Eleonore Erdmuthe was widowed again two years later, after her unfaithful husband contracted smallpox from his mistress. Eleonore remained in Saxony for another two years, until her death in 1696. The orphaned Caroline and William Frederick returned to Ansbach to stay with their elder half-brother, Margrave George Frederick II. George Frederick was a youth with little interest in parenting a girl, and so Caroline soon moved to Lützenburg outside Berlin, where she entered into the care of her new guardians, Frederick, Elector of Brandenburg, and his wife, Sophia Charlotte, who had been a friend of Eleonore Erdmuthe.
On 9 August 1721, Maitland received a Royal Licence that allowed him to test variolation on six prisoners from Newgate Prison. The experiment took place in August 1722, under the direction of Sir Hans Sloane. All prisoners survived, and they were pardoned later that year. One prisoner who was exposed to the disease proved to be immune.
The earliest procedure used to prevent smallpox was inoculation (known as variolation after the introduction of smallpox vaccine to avoid possible confusion), which likely occurred in India, Africa, and China well before the practice arrived in Europe. The idea that inoculation originated in India has been challenged, as few of the ancient Sanskrit medical texts described the process of inoculation. Accounts of inoculation against smallpox in China can be found as early as the late 10th century, and the procedure was widely practiced by the 16th century, during the Ming dynasty. If successful, inoculation produced lasting immunity to smallpox. Because the person was infected with variola virus, a severe infection could result, and the person could transmit smallpox to others. Variolation had a 0.5–2 percent mortality rate, considerably less than the 20–30 percent mortality rate of the disease. Two reports on the Chinese practice of inoculation were received by the Royal Society in London in 1700; one by Dr. Martin Lister who received a report by an employee of the East India Company stationed in China and another by Clopton Havers.
In late 1722, Caroline of Ansbach ordered the inoculation of five orphans of St. James's Parish in London. Following their success, Caroline had Maitland inoculate her eldest son, Frederick and one other child.