Who was president in the 1780's?

The US did not have a president until 1789, George Washington who was the first President of the USA

More correctly: There were Presidents of the United States before the US Constitution defined the current office. Here is a list of who was PRESIDENT OF THE UNITED STATE OF AMERICA in the 1700s

1. Peyton Randolph, September 5 to October 21, 1774 and May 10 to May 23, 1775

2. Henry Middleton, October 22, 1774 - May 9, 1775

3. John Hancock, May 24, 1775 - October 30, 1777

4. Henry Laurens, November 1, 1777 - December 9, 1778

5. John Jay, December 10, 1778 - September 27, 1779

6. Samuel Huntington, September 28, 1779 - July 9, 1781

(The Articles of Confederation were adopted March 1, 1781)

7. Thomas McKean, July 10, 1781 - November 4, 1781

8. John Hanson, November 5, 1781 - November 3, 1782

9. Elias Boudinot, November 4, 1782 - November 2, 1783

10. Thomas Mifflin, December 1783 - June 1784

11. Richard Henry Lee, November 30, 1784 - November 22, 1785

12. John Hancock, (Second Term) November 23 1885 - June 5, 1786

13. Nathaniel Gorham, June 1786 - January 1787

14. Arthur St. Clair, February 2, 1787 - January 21, 1788

15. Cyrus Griffin, January 22, 1788 - April 30, 1789

(The US Constitution was ratified June 21, 1788)

16. George Washington, April 30, 1789 - March 4, 1797

17. John Adams, March 4, 1797 - March 4, 1801