Anonymous [Sir William Butler] (1882) The Invasion of England, told twenty years after by an old soldier, Sampson Low, London
A telling example of this form of apocalyptic novel is the anonymously authored The Invasion of England: Told Twenty Years After, by an Old Soldier, …… The unattributed opening epigraph contains fantastic imagery similar to that of Revelation: “And I saw two hosts conflicting in the air, / And shadows doubtless of the unborn time, / Cast on the mirror of night.” There is the apocalyptic sense of impending violence, as “portents of war were observable throughout the empire, and
the air was filled with rumours of approaching tumult.” This hardly prepares the reader for another turgid account of England’s unpreparedness in the face of unprovoked enemy invasion. [Ernie Hilbert, ‘Preludes to Armageddon: Apocalyptic Clamor and Complaint in Britain, 1850-1914’, Journal of Millennial Studies, Vol. 1 Issue 2. 1999]
There is a biographical article about Sir William Butler in the Dictionary of Canadian Biography but it doesn’t mention this among his works.