Petr Hošek, also known by the stage names Blackie and Blackosh, is one of the founding members of Czech black metal group Root.
The lyrics contain themes concerning magic, nature, spiritualism, and is influenced by Celtic culture and symbolism.
The only album in Cales discography that somewhat deviated from the usual pagan folk metal style and lyrical themes was "Uncommon Excursion" since it was much more in the style of melodic rock with themes/lyrics about life, personal struggles, partying, rock n' roll, and so forth.
According to a recent interview with Petr from February 2019, the project may be on hold or possibly discontinued in the future since he feels that all of the existing Cales albums are enough for now, but time will tell.
In 2022, Cales released Chants of Steel featuring guest vocals from many prolific metal bands.