lwn indicates e16 released on 2000: https://lwn.net/Articles/453699/

changelog indicates e16 released on 1999: https://git.enlightenment.org/e16/e16.git/tree/ChangeLog?h=v1.0.21

changelog indicates e17 released on 2012: https://git.enlightenment.org/core/enlightenment.git/tree/ChangeLog?h=v0.23.1