E. 1999 Eternal is the second studio album by American hip hop group Bone Thugs-N-Harmony, released July 25, 1995, on Ruthless Records. The album was released four months after the death of rapper Eazy-E, the group's mentor and the executive producer of the album. Both the album and single "Tha Crossroads" are dedicated to him. Following up on the surprise success of their breakthrough single "Thuggish Ruggish Bone", it became a popular album and received positive reviews from music critics, earning praise for the group's melodic rapping style. The album title is a portmanteau of the then-future year 1999 and Cleveland's eastside neighborhood centering around East 99th Street and St. Clair Avenue where the group is based.
Upon release, E. 1999 Eternal was met with widespread critical acclaim. Jason Birchmeier of Allmusic described it as "an impressive debut full-length that dismisses any notion that the group was merely a one-hit wonder" and claims that it "maintains a consistent tone, one that's menacing and somber, produced entirely by DJ U-Neek, a Los Angeles-based producer who frames the songs with dark, smoked-out G-funk beats and synth melodies." The Source hailed E. 1999 Eternal as one of The Top 100 Rap Albums of 1990s, giving it a 4 1/2 mic rating. Cheo H. Coker of the Los Angeles Times gave the album a near perfect three and a half stars out of a possible four, stating "This Cleveland-based quartet has raised the stakes of the gangsta rap game, not only in terms of pure, gritty excess, but also in rhyme-style, cadence and delivery. Bone isn't content to just shoot at that next emcee or punk in their neighborhood; they'll harmonize about it too, mixing graphic imagery with old-fashioned street-corner crooning. Essentially, this is a West Coast-style dancehall record, complete with heavy-looped bass lines, electronic gunshots, warped-out dub sounds and fast-paced rhyming style mixed with harmonizing that the Jamaicans call singjay. No change in subject matter: just bloody shoot-'em braggadocio, laced with ominous piano samples. This is the kind of album that starts out good and gets better with repeated listenings--as the dark, subliminal references clear up. Easily one of the most worthwhile rap purchases of the year." In a second thought review by Stylus, the album was described as "Lyrically speaking, Bone Thugs have much in common with countless mainstream rap acts. The themes running throughout E.1999 Eternal are familiar—drugs, violent crime and death make regular appearances. It’s the manner in which the lyrics are framed and delivered that makes the group such a bizarre proposition. Bone Thugs had a melodic flow—frequently delivered in unison—that bordered on singing. They could rap together at a lightning fast pace, without losing their sweetness." Stylus also praised producer DJ U-Neek for his production style on the album stating "The album was entirely produced by DJ U-Neek (although he did collaborate on some tracks), endowing cohesiveness to the unique Bone Thugs sound. U-Neek was, like the vocal group members of Bone Thugs, unorthodox in the rap field. It wouldn’t be far off to describe him as a songwriter as well as a producer. He was always keen to flesh out interesting sounds—usually based around rumbling piano chords, mellotron and synthesised strings. Yet, the focus was largely on song craft and melody—the album frequently strays into gloomy territory, but never loses its sense of tunefulness. The beats were not particularly striking—usually low-key and sluggish, but the album’s strengths are not rhythm-related."