Thomas Jefferson helped to organize the Democratic-Republican Party in 1790.
=== Controversies ======= Burr conspiracy and trial ====Following the 1801 electoral deadlock, Jefferson's relationship with his vice president, former New York Senator Aaron Burr, rapidly eroded
After the Washington administration negotiated the Jay Treaty with Great Britain (1794), Jefferson saw a cause around which to rally his party and organized a national opposition from Monticello

