were sporadic and unorganized during its monopoly period. Although the HBC recognized the potential of vaccination, understanding that more people meant more fur for them, there was no systematic vaccination program in place until the epidemic was well underway. Some vaccines were sent to trading posts early in the 19th century but were left to collect dust. The smallpox infection spiked in 1780s, and persisted up to the 1837 epidemic. In what is now Canada, fur trade strengthened communities such as the Mushego Cree, Anishinaabe, and Ottawa. The Mandan tribe had previously experienced a major smallpox epidemic in 1780–1781, which severely reduced their numbers down to less than a few thousand. Many other bands along the Missouri River suffered smallpox epidemics during 1801–1802 and 1831. Sporadic efforts were made to promote vaccination among the Indigenous peoples since the turn of the nineteenth century. Later, the Indian Removal Act the U.S. Congress took its first step in 1832 to generate public support for vaccination of the Native Americans. But shortly after passage of this congressional act to extend vaccinations to Indians, Secretary of State Lewis Cass stated that no effort would be made "under any circumstances" to send surgeons to vaccinate Indians up the Missouri River beyond the Arikara tribe. This Great Plains epidemic spanned thousands of miles, reaching California, the northwestern coast and central Alaska before finally subsiding in 1840. Epidemic The smallpox epidemic is estimated to have killed 17,000 people along the Missouri River. The St. Peter steamboat, traveled up the Missouri River to Fort Union (North Dakota) from St. Louis (Missouri) and infected people along the way, marking the beginning of the outbreak. The St. Peter made it to Leavenworth, Kansas around April 29. At this time a deckhand showed signs of smallpox. Shortly after three Arikara women joined the ship on their trip back to the Mandan community. Although the women showed signs the infection, they were allowed to return to their village which they then spread to their community. The disease spread to the Mandan people, and was of the most virulent, malignant hemorrhagic form. In July 1837, the Mandan numbered about 2,000; by October that number had dwindled to 23 or 27 survivors by some accounts, 138 by another account, reflecting at least a 93 percent mortality rate. On August 11, Francis Chardon, a trader at Fort Clark, wrote, "I Keep no a/c of the