The band recorded the first one, called Evil Unleashed in the Korsakov studios in Madrid during the summer of 2004 produced by Kosta Vázquez but it was never released due to problems with the label.

In December 2009, Angelus Apatrida signed a worldwide deal with major label Century Media Records and toured with Swedish metal act Arch Enemy in Spain and Portugal.

[3] On 28 October, the band released the music video for Blast Off, directed and produced by Stuff & Nonsense and directors Adriana Lorente and Sara Cort.

But, if we had to choose one song to represent the whole thing, it would be 'You Are Next' because, both lyrical and musically, it showcases the anger and fury we wanted to put into this album, and also reflects the step forward we feel we have made technically.

[5] On 18 September 2013, Angelus Apatrida announced their next European tour in November-December together with Havok and Savage Messiah, supporting their upcoming re-release of the band's first two albums as a double-disc set entitled Evil Unleashed / Give 'Em War, out in Europe via Century Media Records on 18 November 2013.

This marked the first time that their first two albums, Evil Unleashed (2006) and Give 'Em War (2007), were properly made available outside of the band's home territory of Spain.

The creative team involved with this re-release is the same as on the previous two Angelus Apatrida albums, Clockwork (2010) and The Call (2012): Daniel Cardoso handled remastering duties for the material and Gustavo Sazes / Abstrata (Arch Enemy, Firewind, Dream Evil, etc.)

Lead singer, Guillermo Izquierdo commented that he believes that the album is the band's most technical, and the perfect presentation of Angelus Apatrida.

The artwork for Hidden Evolution was handled by Gyula Havancsák / Hjules.com, who has also created album sleeves for bands such as Annihilator, Destruction, Stratovarius, Grave Digger and Nightingale.