Edward Jenner spread around Europe and was used "en masse" in the Spanish Balmis Expedition (1803–1806), a three-year-long mission to the Americas, the Philippines, Macao, China, led by Dr. Francisco Javier de Balmis with the aim of giving thousands the smallpox vaccine. The expedition was successful, and Jenner wrote, "I don’t imagine the annals of history furnish an example of philanthropy so noble, so extensive as this." Napoleon, who at the time was at war with Britain, had all his French troops vaccinated, awarded Jenner a medal, and at the request of Jenner he released two English prisoners of war and permitted
Edward Jenner their return home. Napoleon remarked he could not "refuse anything to one of the greatest benefactors of mankind." Jenner's continuing work on vaccination prevented him from continuing his ordinary medical practice. He was supported by his colleagues and the King in petitioning Parliament, and was granted £10,000 in 1802 for his work on vaccination. In 1807, he was granted another £20,000 after the Royal College of Physicians confirmed the widespread efficacy of vaccination. Jenner was also elected a foreign honorary member of the American Academy of Arts and Sciences in 1802, and a foreign member of the Royal Swedish Academy