The loyal Iron Warriors who escaped to Ultramar are most commonly associated with Barabas Dantioch and the small group that fled with him. In the lore, they were sheltered by Guilliman, fought alongside the Ultramarines during the Heresy era, and were likely either absorbed into Ultramar’s forces or later used as the nucleus for a successor lineage such as the Silver Skulls or a related chapter concept.

What is known

  • Dantioch is the best-known loyalist Iron Warrior, and he escaped with a handful of survivors to Ultramar.
  • They were not simply handed back to Perturabo; the usual fan-reading is that Guilliman protected them and made use of them in the wider war effort.
  • Their exact end is not firmly stated in the main lore, so later fate remains partly speculative.

Most likely outcome

  • They probably continued fighting for the Imperium after reaching Ultramar, at least for a time.
  • A common theory is that they were folded into Ultramarines command structures, then later influenced the founding of a successor chapter.
  • The most frequently mentioned successor connection is the Silver Skulls , though that link is still debated rather than fully confirmed.

In plain terms

They escaped, survived, and kept serving the Imperium for some period, but the books never give a clean “this is exactly how each one died” ending. The safest answer is that their story likely fed into later Ultramar/Second Founding-era legacy rather than ending in a single recorded battle.

TL;DR

The loyal Iron Warriors who made it to Ultramar probably fought on under Guilliman, and their legacy may have helped shape a later successor chapter, but their exact fate is not definitively nailed down in canon.