In America before the Civil War premillennialism of a traditional variety was an important minority position held by some mainline Protestant leaders. It did not differ greatly from the postmillenialism of the same era. Both saw history as controlled by a cosmic struggle, both allowed for interpreting some Biblical prophecies literally, and both thought that some prophecies about the time immediately preceding the millennium were already being fulfilled in current events. They disagreed primarily over whether Christ would come before or after the millennium. The premillenialists were prone to a more literal interpretation of Scripture and were less hopeful concerning progress. During the 1860s, premillennialism of this sort was rapidly rising in popularity.
Source: wiktionary