"We march for Macragge, and we shall know no fear!"

The Ultramarines are considered one of the strongest and most honoured of all the Space Marine Chapters in the Imperium of Man, and were responsible for almost single-handedly holding the Imperium together after the Horus Heresy. Highly disciplined and courageous warriors, the Ultramarines have remained true to the teachings of their Primarch Roboute Guilliman for 10,000 standard years. The Ultramarines were originally the XIII Space Marine Legion before the reforms that initiated the Second Founding and reshaped the Imperium after the Heresy on the orders of Guilliman himself.

The name "Ultramarines" is a nod to both the Chapter's standing amongst the other Space Marine Chapters and their role as the source for the gene-seed of more Chapters of Astartes than any of the other former First Founding Legions combined. The culture of the Ultramarines is loosely themed upon the culture of Old Earth's ancient Roman Empire, as exemplified in their Astartes' pseudo-Latin names and their strict adherence to the Codex Astartes, as well as the society of their homeworld of Macragge and the Chapter's method of recruitment. The Ultramarines directly rule the sector of space in the Eastern Fringe known as Ultramar as a fief of the Imperium and their Chapter Master is also considered the Lord of Macragge and the Master of Ultramar.

Strikeforce Ultra: The Ultramarines[strikeforceultra.enjin.com]