When did the american two-party begin to emerge?

The two party system began to emerge during the ratification of the constitution in 1824, shortly before the Civil War.

United states v.  nixon, 418  u.s.  683 (1974),  was  a landmark  united states supreme court case  that resulted in a unanimous  decision  against president richard  nixon, ordering him to deliver tape recordings  and  other subpoenaed materials to a  federal  district  court.