Alexander Hamilton was the United States' first Secretary of the Treasury, serving from 1789 to 1795. Appointed by President George Washington, Hamilton's tenure was marked by his efforts to establish a stable financial system for the fledgling country. He advocated for the federal government to assume state debts incurred during the Revolutionary War, set up a national bank, and implement tariffs to protect American industry. His financial policies laid the foundation for the U.S. economy and contributed significantly to the establishment of federal authority, making him a key figure in American history.