Upon its release, Mule Variations received widespread critical acclaim. AllMusic reviewer Stephen Thomas Erlewine stated that "the album uses the ragged cacophony of Bone Machine as a starting point, and proceeds to bring in the songwriterly aspects of Rain Dogs, along with its affection for backstreet and backwoods blues, plus a hint of the beatnik qualities of Swordfish. So Mule Variations delivers what fans want, in terms of both songs and sonics" and awarded the album four out of five stars. Former Village Voice editor Robert Christgau gave the album an A– rating and praised Waits' and Brennan's songwriting, saying "together they humanize the percussion-battered Bone Machine sound, reconstituting his '80s alienation effects into a Delta harshness with more give to it." David Browne of Entertainment Weekly said that Mule Variations "restores the wizened humanity — and a more traditional sense of songcraft — to music," gave the album a B+ rating and concluded that Waits was "the last of the classic American tunesmiths." Hot Press reviewer Peter Murphy described the album as "an emotionally forthright record" and called it "a record of at least two minds: scuffed rooming-house madrigals contrasted with big, fat, bleeding heart ballads." Zach Hooker of Pitchfork awarded the album a 9.5 out of 10 rating, describing it as "a great album" and further saying that "sonically, it picks up where Bone Machine left off, but drops some of that album's artifice: the clattering, trebly out-back-of-the-shed sound is still here and the inexplicable presence of Primus persists." Rolling Stone said that the album "contains the most blues of any album made" but added "the problem is that it's more of the same", describing it as "the latest installment of discourse" and awarding the album three out of five stars. Mule Variations was a moderate commercial success. The album charted in 14 countries worldwide upon its release, including debuting at number 30 on the United States Billboard 200 and number 1 on Norway's album chart. The album was certified gold in Canada in July 2001 after selling over 50,000 copies and as of April 2009 had sold more than 500,000 copies worldwide. Mule Variations won the Grammy Award for Best Contemporary Folk Album at the 42nd Grammy Awards and was nominated for Best Male Rock Vocal Performance. In 2010, it was awarded a platinum certification from the Independent Music Companies Association, which indicated sales of at least 500,000 copies throughout Europe. As of 2006, sales in the United States have exceeded 440,000 copies, according to Nielsen SoundScan.
Wings Over Jordan Gospel, Bali Eternal - turntable samples
Christopher Marvin, the son of actor Lee Marvin, was featured as a guest drummer as a nod to Waits' membership in The Sons of Lee Marvin, a humorous secret society of Marvin look-alikes.
