Heavy metal music
Critics disagree over who can be thought of as the first heavy metal band. Most credit either Led Zeppelin or Black Sabbath, with American commentators tending to favour Led Zeppelin and British commentators tending to favour Black Sabbath, though many give equal credit to both. A few commentators—mainly American—argue for other groups including Iron Butterfly, Steppenwolf or Blue Cheer. Deep Purple, the third band in what is sometimes considered the "unholy trinity" of heavy metal (Black Sabbath, Led Zeppelin, and Deep Purple), despite being slightly older than Black Sabbath and Led Zeppelin, fluctuated between many rock styles until late 1969 when they took a heavy metal direction.
Metal Mass
The concept of Metal Mass was thought up by five metal fans, three of whom worked at a church (pastors Haka Kekäläinen and Jukka Valkama and youth worker Mikko Saari) and the other two being musicians (Markus Korri and Juhani Palttala), after a 2005 seminar on the relationship of Church and heavy metal music. They gathered a team for service and began working on arrangements. The first Metal Mass was held around the time of the annual Tuska Open Air Metal Festival, June 29, 2006, in Temppeliaukio Church. Taage Laiho of the hard rock band Kilpi, was the lead singer in that Metal Mass. The service was reportedly a success, with 300 people being left out because of safety reasons.