Alius Rex - Book 1 (2006)

Alius Rex is an alternate history comic book series by Kevin Grevioux, published by DarkStorm Studios. It is illustrated by Gabriel Guzman and Javier Tartaglia.
The series takes place in an alternate Britain in the late tenth century. King Nigel of the fictional Kingdom of Northwind faces invasion by a coalition known as the Mammonites, led by a warlord named Orlik on behalf of a mysterious "foreign king," called Alius Rex in Latin. When the Mammonites invade Northwind, it is revealed that Orlik has allied with alien invaders who are possessed of technology far in advance of medieval Earth's.