1570s, "pertaining to Elysium (q.v.), the abode of the blessed after death." Hence, "exquisitely happy, full of the highest bliss."
Entries linking to elysian
Elysium n.
1590s, from Latin Elysium, from Greek Ēlysion (pedion) "Elysian field," abode of the blessed after death, where heroes and the virtuous dwell, which is of unknown origin, perhaps from Pre-Greek (a non-IE substrate Mediterranean language). Also used figuratively of a situation of complete happiness.