There is more than one artist with this name:

1)Latvian gothic-electro-rock project. Artūrs Bērziņš (stage-name: Christian) began in 1998 with project „Angel’s Tears”. In 2005 decided to rename project to Diadema.
Christian – vocals, programming, guitars, keys
Mora Amaiu – vocals.
Herman - guitars
Eve Noir - violins
Music and lyrics by Christian


2)Diadema is one of the only heavy metal bands of the Albanian nation. They hail from Prishtina, Kosovo. They were formed in 2001 and are currently signed with Maestro Productions label. Though fans declare they are in competition with the band Troja which is considered the best Albanian metal band at the time being.
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