Photonuclear reactions: Past, present, and future

This contribution is supposed to provide an introduction to the discussion of future research opportunities at the planned {gamma}-ray beam of the ELI-Nuclear Physics pillar. It contains a brief overview on the history of photonuclear science, some fundamental facts on photonuclear reactions at energies below 20 MeV, a few examples for recent photonuclear research, and a brief outlook to a future with ELI-NP.