Lief began as "lēof" in Old English and has since appeared in many literary classics, first as an adjective and then as an adverb. It got its big break in the epic poem "Beowulf" as an adjective meaning "dear" or "beloved." The adverb first appeared in the 13th century, and in 1390, it was used in John Gower’s collection of love stories, "Confessio Amantis." Since that time, it has graced the pages of works by William Makepeace Thackeray, Alfred Lord Tennyson, and D.H. Lawrence, among others. Today, the adjective is considered to be archaic and the adverb is used much less frequently than in days of yore. It still pops up now and then, however, in the phrases "had as lief," "would as lief," "had liefer," and "would liefer."
First Known Use of lief
before the 12th century, in the meaning defined at sense 1