Steve Harris, the bassist of the band, formed the group in 1975. He attributes the name to a moovie based on a novel called, The Man In The Iron Mask. Their original singer, Paul day, was kicked out for the lack of fire in live performances. He was replaced by dennis wilcock, who had a friend by the name of Dave Murray. This made former guitarists, Dave Sullivan and Terry Rance unhappy, which led to the band temporarily breaking up in '76. They formed the band agian, but this time with only present-day guitarist Dave Murray.
In '77, Iron Maiden recruited Bob Sawyer. He was going to be rhythm guitar for the band until they had a poor concert which resulted in the firing of the entire band (including the makeshift lineup of Tony Moore on keyboard, Terry Wapram on guitar, and Barry Purkis on drums. Dave Murray was reinstated shortly after, and Doug Sampson was hired to play drums.
In 1978, a chance meeting happened at the Red Lion Pub in Leytenstone, which gave singer Paul Di'Anno a chance to succesfully audition for the band. On new years eve 1978, the band recorded demos of four songs including future hit Prowler. Their first appearance on an album was on Metal for Muthas, which included early versions of songs such as Wrathchild and Sanctuary. From late 1977 to '78 Dave Murray was the sole guitarist until Paul Cairns joined. Paul shortly after left the band, and even though the band originally Wanted Murray's childhood friend Adrian Smith, they had to settle with Dennis Stratton.
Right when Stratton jined the band, former drummer Doug Sampson was replaced by Clive Burr. In 1979, the band got into a record deal with EMI. In 1980, Iron Maiden's Self-Titled release shot to Number 4 on the UK charts in just a week. The album had such songs as Iron Maiden, Running Free, Transylvania, Phantom of the Opera, and Sanctuary. In '80, the band opened for KISS on their Unmasked tour. After the tour Dennis stratton was released and replaced by Adrian Smith. In '81 the band released their second album Killers which had songs like, Prodigal Son, and Murders in the Rue Morgue.
In '81, Iron Maiden released former singer Paul Di'Anno, because of said drug usage which effected his performance. They found Bruce Dickinson, who auditioned for them in September 1981, and joined the band shortly after. Dickinson's recorded debut with Maiden was called, The Number Of The Beast, which claimed the band's first ever Number 1 on the UK charts. An American Political Lobbying Group claimed that Iron Maiden was satanic because of their albums names. This led to controversy in the bands U.S. leg tour of The Number Of The Beast.
In December 1982, Clive Burr (drummer) ended his being with the band, and he was replaced by present-day drummer Nicko McBrain. In 1983 the band released Peace of Mind, which reached number 3 on the UK charts, and number 70 on the U.S. charts. The album had hits such as, The Flight Of Icarus, and The Trooper.
Shortly after the release of Peace of Mind, the band released Powerslave. The album featured songs such as, 2 Minutes to Midnight, Aces High, and Rime of The Ancient Mariner, the song based on a poem by Samuel Taylor Coldridge, which ran over 13 minutes long. The tour following the album, named The World Slavery Tour, was the bands largest tour to date, consisting of 193 shows in 13 Months. It was one of the largest tours in music history playing to over 3,500,000 people.