George Catlin was an American painter who traveled extensively among Native American tribes in the 1830s. He painted nearly 500 portraits of Native Americans to document their lives and culture before they were displaced by white settlers. Catlin believed there were two types of Native Americans - the original character who lived traditionally, and the secondary character who had been influenced by white culture. His paintings provide a visual record of Native American tribes like the Pawnee, Mandan, and Ojibwa before significant cultural changes due to westward expansion.