Devils and Stump lakes in eastern North Dakota have been diminishing in area more or less continuously since the land around them was settled in the 1880's. Desiccations similar to the current one have occurred at least once and possibly two or more times in the past and are indicated directly and indirectly by tree stumps recently uncovered as the lake water receded and by lacustrine deposits containing buried soils and vertebrate remains. The lake levels seem to respond in a very sensitive manner to slight climatic changes. Probably the present desiccation and certainly the ones in the past are the result of changes toward a drier and warmer climate. The first may have been synchronous with the Thermal Maximum. A high abandoned strand line and associated lacustrine deposits containing buried soils and vertebrate remains indicate at least one period in the postglacial past, possibly following the Thermal Maximum, that was wetter and cooler than the present. A second desiccation, more definitely established and based on the radiocarbon dating of a tree stump, occurred less than 700 years ago, possibly during the sixteenth century.