Green’s Dictionary of Slang

peace phr.

[popularized by hippies; mostly in ironic or historical use since]

(orig. W.I.) farewell, goodbye, a greeting.

[WI]L. Bennett ‘Writing Home’ in Jamaica Dialect Verses 23: Him jus’ hole-up him han’ like dis an genkly halla – ‘Peace’.
[WI]R. Mais Hills were Joyful Together (1966) 250: Ras said: ‘Howdy brother. Peace an’ love.’.
[US]J. Simon Sign of Fool 189: ‘Peace, man,’ I called after him. ‘Peace.’.
[US]P. Maas Serpico 196: Some of them would smile or nod at him, and say ‘Peace, brother’.
[WI]M. Montague Dread Culture 14: A Rastaman walked up, greeting them, ‘Rasta love, Brother Butty. Peace, youthman.’ ‘One love, Iyah Nyah,’ Uncle Butty responded.
[UK]Observer Rev. 9 Apr. 5: Peace, everyone.
[SA]Mail & Guardian (Johannesburg) 24 Sept. 🌐 Peace, y’all. Legalise it.