Despite signing a major label deal with Capitol Records, the band declined to promote it extensively but nevertheless shot a video for "Carolyn's Fingers" which was issued as a single only in the US.

[11] The band took on new familial responsibilities as bassist Simon Raymonde married his first wife, Karen, and vocalist Elizabeth Fraser was expecting her first child with guitarist and co-founder Robin Guthrie.

[12] The latter's cocaine habit previously "escalated" during the recording process for Blue Bell Knoll;[13] Fraser and Raymonde believed that the new baby would prove a diversion from Guthrie's dependency and allow the pair to "play happy families.

"[12] Their wishes did not pan out, with Guthrie relying heavily on drugs as the band developed Heaven or Las Vegas, causing him to experience "deep" paranoia and mood swings.

[15] Of her pregnancy, Fraser said that she gained clarity about what mattered to her most: "Suddenly I had confidence which I'd never ever had in my life, which I consequently lost after I had the baby, because it's such a frightening experience you lose it again and you have to start over again.

He recounted: "I was only 27, I was still quite young and he was a very influential guy for me so that was a big blow but, looking back on it, having a major life event happening probably helped the record have that edge to it.

[12][17] Despite most of Fraser's lyrics "[emerging] in alien tongues", which she sums up as "laziness" and "bad diction", she attributed the album's more identifiable words to Lucy Belle's influence.

[15]There was salvation in [Fraser's vocals and lyrics] too, in terms of helping save her relationship with [Guthrie], the joy of bringing a baby into the world that they could love.

[10] Despite being in a "very good space musically" and describing the recording process as an "inspirational time", Raymonde said: "It was trying to mask all the other shit that was going on that we didn't want to stop and think about for too long".

[19] Paul West, of the design studio Form, previously worked with Cocteau Twins on the cover for Blue Bell Knoll.

[19] The final artwork is a long exposure of Christmas tree lights against a colour backdrop, with its typography produced by hand on an acetate overlay.

[26] The album subsequently featured in the magazine's "best of the year" roundup: "It's wonderfully comforting how the Cocteaus continue on their inimitable course, blissfully regardless of what's going on in the world outside their surreal reality".

[32] Andrew Perry of Select wrote that, Heaven or Las Vegas is the Cocteau Twins in their "usual, spectacular and enigmatic context".

[29] Vox's Roger Morton wrote, "In times when every other pop group is dragging on board whatever chemicals, '60s techniques and hypno-rhythms they can grab in order to achieve the desirable blissed-out condition.

[35] It was considered the band's strongest work since Treasure by AllMusic reviewer Ned Raggett, who called it "simply fantastic" and successful in creating "more accessibility".