Before his music career began, Allen was a jouster at a Medieval Times Dinner Theater. He was introduced to the band Symphony X by former singer Rod Tyler. Allen has been the lead singer of Symphony X since 1995, releasing eight studio albums and one live album with the band. His first solo album, Atomic Soul, was released April 25, 2005. As well as singing he also plays the bass when performing songs from Atomic Soul live. He is referred to in various circles as "Sir Russell Allen", and he is credited as such on Arjen Lucassen's Star One albums, because of a joke that Arjen made regarding Allen's former job as a jouster. In the summer of 2005 he went on tour with Symphony X on Dave Mustaine's Gigantour alongside such bands as Dream Theater, Megadeth, and Nevermore. The same year, he also made part of a duo melodic rock project with singer Jørn Lande called Allen/Lande, which has four albums, all released by Frontiers Records. In addition to being Symphony X vocalist, he is also currently working in another band with guitarist Mike Orlando called Adrenaline Mob. In November 2013, Allen joined Trans-Siberian Orchestra for their 2013 Fall/Winter tour and performed with the group at the Wacken Open Air 2015. He is also featured in their 2015 studio albumLetters From the Labyrinth. In 2014, a new project was announced, featuring Russell Allen with bassist Mat Sinner and other members of the German band Primal Fear, called Level 10, with an album release slated for January 2015. The release date and the name of the album were revealed in November 2013: it would be titled as Chapter One, to be released on January 23, 2015 in Europe and on January 27, 2014 in North America via Frontiers Music srl. In 2015, Russell Allen recorded vocals for a new project of Whitesnake and former Night Ranger guitarist Joel Hoekstra called Joel Hoekstra's 13, with an album called Dying to Live, released on October 16. Russell sings lead vocals on half of the songs in the album with background vocals and the other half of lead vocals recorded by Jeff Scott Soto. In 2020, Russell Allen collaborated with former Nightwish vocalist Anette Olzon on a new a duo melodic rock project under the name Allen/Olzon. Worlds Apart, their debut album, was released on 6 March 2020.
Musical style
Multi-instrumentalist, singer and composer Arjen Lucassen has said the following regarding Russell Allen: Allen has worked with Lucassen on various occasions: originally he sang the song "Dawn of a Million Souls" on Ayreon's 2000 album , and in 2002 he became one of the lead vocalists for Lucassen's project Star One. Allen has stated in an interview that "Ronnie James Dio is definitely at the top of my list of influences" and also mentioned Bruce Dickinson of Iron Maiden and former Free and Bad Company singer Paul Rodgers as influences.