Erik Erikson was a German developmental psychologist born in 1902 who developed one of the most widely accepted theories of psychosocial development. He was influenced by Sigmund Freud and studied at Harvard, Yale, and the University of California at Berkeley. Erikson's theory proposed 8 stages of psychosocial development from infancy to late adulthood, where individuals must resolve crises of trust, autonomy, initiative, industry and more. His stages model influenced many other theorists and helped inform teaching approaches focused on identity development.