The album's title refers to the "H blocks" at Maze Prison (also known as "Long Kesh") in Northern Ireland, where Irish republican prisoners were held during the Troubles. The subject matter of several of these songs (particularly Moore's "90 Miles From Dublin") specifically centers on the period of the blanket and dirty protests at Maze and at Armagh Women's Prison. The launch of the album was raided by the Special Detective Unit ("Special Branch") of the Republic of Ireland.

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