The history of the United Baptists was the union of the Regular Baptists and Separate Baptists in the late 1780s to 1800s, and includes those churches that have continued in the same faith. Both Kentucky and Virginia established a general union of the United Baptists. Virginia was the first state to officially form a union in 1787 while Kentucky's union was finalized in 1801. Although North Carolina started uniting Regular and Separate Baptists as early as Aug. 1777, they didn't take the name "United" upon their churches until the Kehukee Association did in 1788.
"To prevent the Confession of Faith from usurping a tyrannical power over the consciences of any, we do not mean that every person is bound to the strict observance of every thing therein contained; yet that it holds forth the essential truths of the gospel, and that the doctrine of salvation by Christ, and free and unmerited grace alone ought to be believed by every Christian, and maintained by every minister of the gospel. Upon these terms we are united and desire hereafter that the name of Regular and Separate be buried in oblivion, and that from henceforth we shall be known by the name of the UNITED BAPTIST CHURCHES IN VIRGINIA."
This is the first printed statement that declares the union between Regular and Separate Baptists has become, in fact, United Baptist. The Virginia Confession of Faith has been held to by many associations. In the first line of the statement, you'll notice that there was a "conflict" with the confession of faith. This conflict kept the two denominations from joining together earlier. The Separate Baptists did not want a confession or articles of faith ruling over them.