I got this on Darkest Hour's 15 year anniversary tour, The Legacy Tour, which featured Revocation, Periphery and Veil Of Maya. They played a badass local indoor skatepark called Area 702 before it closed down.
Darkest Hour was a band that meant a lot to us when I was a kid in high school and the Hidden Hands of a Sadist Nation is still one of my all time favorite records. The album features guest vocals by Tompa and guitar spots by Anders Björler (At The Gates, The Haunted), Peter Wichers (Soilwork) and Marcus Sunesson (The Crown) all of which are obvious influences Darkest Hour had at the time.
The show ended with them playing the instrumental 'Veritas, Aequitas' which is just fucking epic - if you haven't listened to it go check it out, Wichers and Sunesson absolutely rip on there.
The shirt itself is of the cover of the Hidden Hands of a Sadist Nation album, with the Darkest Hour logo thrown in. It has an excerpt of the lyrics from the song 'The Sadist Nation' written backwards.