1967 年在洛杉矶成立的 Iron Butterfly 乐队是重金属乐队的雏形，原始阵容为 Doug Ingle（风琴兼主唱，生于 1947 年 9 月 9 日）、Ron Bushy（鼓手，生于 1941 年 9 月 23 日）、Lee Dorman（贝司手，生于 1945 年 9 月 19 日）和 Eric Braunn（吉他手，生于 1950 年 8 月 10 日），另一位吉他手 Danny Weiss 在录完乐队的第一张专辑《Heavy》后，就离开了乐队。
1968 年专辑《Heavy》出版后，他们在美国主要城市进行了一个多月的巡回演出。该乐队激烈的节奏部分，超重的演唱风格使当时的乐迷大开眼界，所到之处受到了歌迷狂热的欢迎，舆论界和唱片工业都认为他们是潜在的超级巨星。他们的第 2 张专辑《In - A - Gadda - Da - Vida》的成功是前所未有的，其中一首 17 分钟长的同名曲成为重金属音乐的第 1 首经典作品。直到今天，该专辑仍是 Atlantic 唱片公司最伟大的摇滚专辑——也许也是该公司销量最大的唱片之一。因为到 1993 年时，该专辑已经令人不可思议地卖掉了 2500 万张。
1969 年，Braunn 也离开了乐队，两位吉他手 Mike Pinera 和 Larry Rheinhardt 取代了他们的位置。但新吉他手的加盟并未使他们的新专辑《Live》和《Metamorphosis》达到一个新的水准，尽管这两张专辑的销量都很不错。这一切都预示着该乐队已经开始走下坡路了。
1971 年，乐队陷入困境，最明显的迹象就是他们开演唱会的场地由体育场改为只能容纳三五千人的剧场，于是他们决定解散乐队。 1971 年 5 月 23 日他们的告别巡回演出结束后，乐队成员就分道扬镳了。
3 年后，在 Braunn 和 Bushy 的领导下，重组的 Iron Butterfly 东山再起。此时的贝司手是 Phil Kramer，同时还增加了键盘手 Howard Reitzes。他们一起录制了两张畅销专辑《Sun And Steel》和《Scorching Beauty》。此后，乐队再度解散。
在默默无闻 14 年后，Doug Ingle、Ron Bushy、Lee Dorman 和 Eric Braunn 在洛杉矶举行了一场音乐会。他们从中得到了很多快乐和兴趣，于是决定重组 Iron Butterfly。 1988 年，他们又举行了美国 50 个城市的巡回演出。
The band was formed in 1966 in San Diego and released their debut album, Heavy, in 1968, after signing a deal with ATCO, an Atlantic Records subsidiary. The original members were Doug Ingle, Ron Bushy, Jerry "The Bear" Penrod, Darryl DeLoach and Danny Weis. All but Ingle and Bushy left the band after recording the first album in late 1967; the remaining musicians, faced with the possibility of the record not being released, quickly found replacements in bassist Lee Dorman and guitarist Erik Brann and resumed touring.
Weis and Penrod almost immediately went on to form the supergroup Rhinoceros.
The 17-minute "In-A-Gadda-Da-Vida", the title track of their second album, became a Top Thirty hit in the US. (Doug Ingle is reported to have said the title was an alcohol-slurred version of "In the Garden of Eden", although this is probably apocryphal; see the page on that song for more.) The members when In-A-Gadda-Da-Vida was recorded were Doug Ingle (keyboards and vocals), Lee Dorman (bass guitar), Ron Bushy (drums) and Erik Brann, also Braunn (guitar). The next album, Ball, was less successful, and more lineup changes followed. In 1970 with Erik Brann gone, Iron Butterfly released their fourth album, Metamorphosis with two new members, guitarist / vocalist / songwriter Mike Pinera (whose Blues Image had opened for the Butterfly's Vida tour and who later led Ramatam and played with Alice Cooper) and guitarist Larry "Rhino" Reinhardt. The album only managed to get into the top twenty. The band broke up in 1971. Dorman and Reinhardt later became members of the supergroup Captain Beyond.
The band was booked to play at Woodstock, but got stuck at an airport. When their manager called the promotors of the concert, they explained the incredible situation they had been dealt and asked for patience. However, the manager demanded that the Butterfly be flown in by helicopter whereupon they would "immediately" take the stage. After their set they would be paid and flown back to the airport. The manager was told that this would be taken into consideration and he would be called back. In truth, his outrageous demands were never given a second thought.
The band re-formed in 1974 with Ron Bushy and Eric Brann joined by bassist Philip Taylor Kramer and Howard Reitzes. (Kramer later made news with his 1995 disappearance and the discovery of his bones and minivan at the bottom of Decker Canyon in 1999). The albums released during this lineup: Scorching Beauty in 1975 with Reitzes and Sun and Steel early 1976 with DeMartines.
A very brief semi-reunion in 1978, enlisting Jimi Henderson on vocals and former Van der Graaf Generator / The Koobas / Juicy Lucy bassist Keith Ian Ellis, imploded during a tour of Germany, when Ellis was found dead in a motel room.
The famous line-up of In-A-Gadda-Da-Vida got together for the Atlantic Recording Corporation's 40th anniversary concert and celebration, appearing on stage along with the surviving members of Led Zeppelin, and with Aretha Franklin among many other acts of the company's roster in 1987.
On October 3, 2002, original guitarist/vocalist Darryl DeLoach died of liver cancer at the age of 56.
On July 31, 2003 Erik Brann died of cardiac failure at the age of 52. He had released a new CD album just a few weeks before.
As of 2004, the group is once again re-formed, and is touring with early members Ron Bushy and Lee Dorman. Iron Butterfly is now working on a new album that should be released in mid-late 2007.
2. Unconscious Power
3. Get Out Of My Life, Woman
4. Gentle As It May Seem
5. You Can't Win
7. Look For The Sun
8. Fields Of Sun
9. Stamped Ideas