Louis Henry (1911 – 1991) was a French historian. He was the founder of the historical demography and one-place study fields. His 1956 book co-written with , Des registres paroissiaux à l'histoire de la population. Manuel de dépouillement et d'exploitation de l'état civil ancien laid the foundation for studies in those areas.
Henry proposed that it was possible to reconstruct the population of France from 1670 to 1829. He devised more advanced methods and extracted data from records in order to correct bias and indicate which family histories could be used for different kinds of statistical analyses.
Henry is also responsible for the concept of natural fertility, which guided the way demographers have come to understand the idea of fertility control.