A Warden was an officer rank of the Blood Angels Space Marine Legion during the Great Crusade and Horus Heresy eras of the late 30th and early 31st Millennia. The Blood Angels Wardens' existed outside their Legion's normal command structure, and the position was a relatively rare rank within the IX Legion, granted only to the most senior of Veterans.
The Wardens essentially served as guardians of their fellow Blood Angels, often as mentors and guides for the newer Astartes of the Legion but also responsible for upholding the traditions and laws of the IX Legion. Yet, their role was fluid and undefined, and their duties could include advising a company Captain on a matter of tactics, recovering the wounded and dead or leading a ritualistic ceremony of remembrance for fallen Battle-Brothers.
They served as lore-keepers, counsellors, and teachers. In the deep past, men who had served in similar roles in other militaries had been known as diaconus, zampol, chaplain or a dozen other names -- some political, some religious, some secular. The Blood Angels' Wardens existed outside the Legion's chain of command but still within its ranks, maintaining that most Imperial of ideals throughout the Legion -- unity.
Following the Council of Nikaea, it was the Wardens who were charged with upholding the Emperor's Decree Absolute ordering the dismantlement of the Legion's Librarius Division and the restoration of all the Legion's Librarians to line duty where they were forbidden to use their psychic abilities.
Because of this duty and the Wardens' use of black Power Armour and the Crozius Arcanum as signs of their office, it is clear that their rank eventually evolved into the first Chaplains of the Blood Angels and their Successor Chapters.
- Dahka Berus - Dahka Berus was the High Warden of the Blood Angels during the Great Crusade and Horus Heresy eras. As High Warden, it was his duty to make sure that the edicts of the Council of Nikea were strictly enforced as well as act as the spiritual adviser to the Blood Angels Primarch Sanguinius. He participated in the Signus Campaign during the Heresy.
- Yason Annellus - Yason Annellus was a Warden of the Blood Angels at the time of the Horus Heresy. During the Signus Campaign, Annellus barely held back the Red Thirst and took part in the attack on the Cathedral of the Mark on Signus Prime. In that assault Annellus was knocked off his Mastodon transport and torn apart by Daemonettes.
- Arkhad - Arkhad was a Warden of the Blood Angels during the Great Crusade and Horus Heresy eras. The Seneschal and commander of the Legion's garrison on Baal after Sanguinius left with the main force of the Blood Angels Legion on the Signus Campaign, Arkhad and his small force oversaw the planet's transformation into a major hub of Loyalist activity and refuge following the Drop Site Massacre. In the wake of that great betrayal, Arkhad proved immensely distrustful of everyone, and even considered the Salamanders Legion Cruiser Ebon Drake to have been Traitors for their suspicious behaviour in trying to requisition supplies and intelligence.
- Fear to Tread (Novel) by James Swallow, pp. 70-76, 92-98
- Lost Sons (Short Story) by James Swallow
- The Horus Heresy: Book Six - Retribution (Forge World Series) by Alan Bligh, pp. 35-38