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Tree mortality events that have occurred in the eastern hardwood forest during the last century were examined to determine whether there is a relationship between patterns of mortality over time and current patterns of atmospheric pollution. A review of the literature indicates that the apparent increase in the decline and mortality of many hardwood species during the last few decades may be due to intensification of reporting and to the maturation of the forest itself. Most of the mortality is attributed to abiotic and biotic stress factors such as weather, silviculture, and damage by insects and diseases. There is evidence of damage to hardwoods by atmospheric pollutants from point sources such as smelters, and to eastern white pine by ozone. There is no conclusive evidence of an association between patterns of hardwood mortality and regional atmospheric pollution. An extensive list of references covering the major recorded mortality events in the eastern hardwood forest is presented. Also included is a discussion of the distribution of the major eastern hardwoods, changes in the forest that have occurred since the European settlement, and possible effects of these changes on the eastern hardwood forest.