February 15— U.S. Representative Roger Griswold (Fed-CT) beats Congressman Matthew Lyon (Rep-VT) with a cane after the House declines to censure Lyon earlier spitting in Griswold's face; the House declines to discipline either man. 
April 7 – The Mississippi Territory is organized by the United States, from territory ceded by Georgia and South Carolina; later it is twice expanded, to include disputed territory claimed by both the U.S. and Spain (which acquired territory in trade with Great Britain). 
May 23 – Irish republicans and nationalists, known as the Society of United Irishmen, launch a rebellion against British rule, in expectation of greater support from France, which only sends 1,100 men. The United Irishmen are unique amongst Irish nationalist movements, in that they unify Catholics and Protestants around republican ideals. The rebellion rages sporadically, but is defeated by the British by October.
June 18— The first of the four Alien and Sedition Acts, the Naturalization Act of 1798, is signed into law by U.S. President Adams, requiring immigrants to wait 14 years rather than 5 years to become naturalized citizens of the United States. On June 25, another law is signed authorizing the imprisonment and deportation of any non-citizens deemed to be dangerous. 
August 18 – John Lewis Gervais, American revolutionary, member of Provincial Congress (1775), State’s Committee of Safety (1775-1781), South Carolina Senate (1781, 1782), Continental Congress (1782, 1783) (b. 1741)