Only 6 years ago, in 1856 anno domini, the church had been in an uproar. The Circulo Romano, (a secret society of Italian nobles who sought to first rule Rome, then the world, and were thought eliminated by the agents of Pope Pius IX) had emerged from hiding. Assassinating Pius, and exerting their influence to replace him with their own, an intense, charming, and zealous man, who would assume the title of Divinicus I.
This new Pope called for a Holy War against all those who would not show their faith in the One True God, while the Circulo Romano stirred the common folk of Europe into a frenzy, much as they had done all those years ago. Hearing that all their troubles stemmed from those that rejected God, the people joined the Church's cause without hesitation. The Vatican Legion took in an immense number of recruits that year, and moved against the few remaining heathen lands with great haste, subduing one after the other, leaving a bloody trail of destruction, rape, and fire across the countryside as a warning to all who would oppose God's Will.
Their advance was soon, however, despite all their power, stalled by unexpected events. While marching upon the still Gallic kingdom of Ardenne, in the North-East of what may have one day become France, an entire battalion was swallowed by the earth itself. Only days later, pilgrims traveling to the site of a recent apparition in Lourdes, also recently captured, was hit by sudden storms and flooding, killing the 30-something people present. In Venice, the proposed Clocktower of St Mark's, a wondrous display of unparalleled engineering, was only a week away from completion when the boiler exploded, sending cogs, gears, and bricks flying across the nearby streets. One of these crashed through the roof of the the Patriarch's bedchamber, killing him while he slept.
More of these catastrophic events followed, and panic began to rise amongst the Faithful. Surely, if God's good works were being undone by these wild events, He must be working against them Himself!
Divinicus could offer only one explanation to placate his worried followers. These disasters must surely be the work of those who would subvert His Divine Might with impunity! The only targets to blame were the Wizards! They cavort with demons, and drink the blood of men! They had always known it, but the previous leaders of the Faith had sat by, idle, while the soulless mages garnered more power. They were to blame as much as any other of the Faithless. Moreso!
But they are only men, no matter what gifts the devil may grant them! The Vatican would march against them, and they would succeed, for the efforts of all righteous men would win out, and the taint of such blasphemous evil on Eorope's holy soil would be cleansed forever!
From Ardennes, the men marched to the north of the Kingdom of Picarde, took their ships, and became privateers. The more they captured, the more would capture others, and the seas were soon bright with the white and red sails of the Faithful. They would reach England in short order, and the British navy would be hard-pressed to repel them, had they even a choice to.
It was not England that the Vatican sought to capture, however, but the Towers of Arcana situated inside the walls of Old London.
Many ships were swallowed by wind and wave, though the vast majority made safe landfall. Once there, aid was granted to the Vatican Legion by fearful british seeking to prove their Faith. Divinicus issued a papal edict that amnesty would be granted to any british citizen who would join their cause, and work against the vile magicians.
Few would resist such a display of power, and many gave what hospitality they could to the horde of zealots. Some, who had known their local wizards for many years, would not bow. The Vatican Bishops made examples of these, ordering the Legion to stand down while they proved God's Might. They unleashed divine power in vast torrents, hostile spell energies decimating the smaller towers and the surrounding areas. Angels were called down from the Heavens above to slaughter the citizens as the Legion watched, Bishops in oratory, telling the troops to stare in awe at God's Servants, that one day they may ascend to Heaven and stand beside them.
When they reached Old London, however, the Legion found the fight harder going. Many of the Wizards from the outlying areas had fled here already, being forewarned that the Legion was after their blood. They had mustered in the city, all of them Masters of the Arcane, ready for the last defense against insurmountable odds.