[13] This was also the only studio album with guitarist Dennis Stratton, who, having been brought in as a last-minute placement, was dismissed due to "musical differences" after the band's European tour in support of Kiss.

[14] Suspicions were first raised during Iron Maiden's recording, when Stratton added Wishbone Ash-esque harmony guitars and backing vocals reminiscent of Queen to "Phantom of the Opera", of which the rest of the band immediately disapproved and had removed.

[15] Although Stratton stated that he was not "trying to push the band in a new direction",[15] Harris commented that it "really pointed up the difference between Den and us",[16] after which he began to notice that "Dennis was so much more into playing stuff like "Strange World" than he was "Iron Maiden" or "Prowler", because it was more slow, melodic ... when he was soloing on one of the heavier songs, it wasn't with quite the same passion".

[15][17] The 1998 remastered album differs from the original with the addition of the song "Sanctuary", which had then been released only as a single in the UK in May 1980,[18] although it did also appear in the later US version of Iron Maiden, which was issued in August 1980.

"[24] According to Classic Rock and Metal Hammer contributor Dave Ling, writing in the Metal for Muthas CD re-issue liner notes, "Sanctuary" was originally penned by guitarist Rob Angelo (Bob Sawyer), a member of Iron Maiden in 1977, who was paid £300 for the song's rights.

[27] Although "Strange World" is credited solely to Harris, Paul Day, the band's original vocalist from 1975 to 1976, asserted that he also contributed to the song.

[6] "Transylvania" is an instrumental piece composed by Harris, which was later covered by Iced Earth on the album Horror Show.

[10] Iron Maiden spent an initial fifteen weeks on the UK chart, and a further two when it was reissued on EMI's budget subsidiary Fame in 1985.

AllMusic proclaims that it "would still rank as a landmark even if the Dickinson years had never happened" and says there was "no better place to hear how both punk and prog rock informed the new wave of British heavy metal".

[12] Sputnikmusic describes it as "one of the top debut albums in the world of heavy metal", containing "the raw, aggressive power [that] defines the early years of the band".