Seismic activity of a region is directly related to information known about earthquakes (EQs) occurred in the region. An uncertainty may always be associated with determination of seismic activity due to incomplete information about historic EQs. For reliable estimation on return period of major to great EQs, accurate information on seismic history is of utmost importance. In addition, for major to great EQs, reliable estimation about return period is utterly dependent on accurate seismic history. The present work provides a review on methodologies which can help in understanding the seismic history of individual EQ based on both on-fault and off-fault evidences as practiced globally. The geomarkers used for such studies are generally preserved in the sediments and thus in geological records. Study of preserved sediments and features can help in understanding the geometry of the fault and nature of EQ phenomenon. In addition, relevance of such methodologies in understanding the revised seismicity as well as change in return period of major to great EQs, based on detailed review of work performed in the northeast India, is also presented here.