Abstract Prior to 1970 there were fewer than 10 seismographs sited in the southeastern United States—a study region defined herein as all of the states of West Virginia, Virginia, North Carolina, South Carolina, Georgia, and Alabama and the eastern portions of Kentucky and Tennessee (see Sibol and others, 1986, for a detailed description). Multistation seismic networks began to be installed in 1974, and by the end of 1977 there were 53 operational seismograph stations. As of January 1986, the Southeastern U.S. Seismic Network (SEUSSN) Seismicity Bulletin (Sibol and others, 1986) listed 147 stations in the region (Fig. 1). Thus, several years of instrumentally monitored seismicity data for the region have been acquired to supplement the historical data base that extends back to as early as 1698. The purpose of this chapter is to review the seismicity of the southeastern United States as documented by the studies to date of the historical and network data bases. Data acquisition and analyses are derived in large measure from the collective and individual efforts of the members of the SEUSSN coalition—a group of some 10 member institutions that operate seismographs in the region (Sibol and others, 1986). We divide consideration of the data base into a Historical Seismicity period (pre-network: 1698 to June 30, 1977), and a recent period of Instrumental Seismicity (post-network: July 1, 1977 to January 1, 1986). The reasons for that division are the differences in the levels of completeness and accuracy with respect to earthquake size and location. Prior to the