What cluster gas expulsion can tell us about star formation, cluster environment and galaxy evolution

Violent relaxation -- the protocluster dynamical response to the expulsion of its leftover star forming gas -- is a short albeit crucial episode in the evolution of star clusters and star cluster systems. In this contribution, I survey how it influences the cluster age distribution, the cluster mass function and the ratio between the cluster mass and the stellar mass. I highlight the promising potential that the study of this phase holds in terms of deciphering star cluster formation and galaxy evolution, and (some of) the issues which are to be dealt with before achieving this goal.