Iain Alpin is a pivotal and controversial figure in the Grand Duchy of Dael Riata, serving as both the Steward to King Alasdair V and the Commander of the King's Lifeguard.

Born in 735, Iain is the third son of Sean Alpin, the 7th Earl of Ardmor. Despite his noble lineage, he has a fractured relationship with his family; he is currently disowned by his father for “having changed sides,” presumably referring to his unswerving loyalty to the King over his father's more traditional noble interests. He is a veteran who distinguished himself in battle before taking his current post.

He is described as a tall, muscular man who typically wears a green suit decorated with gold braid and the badge of the King's Guard. In his capacity as Commander, he is rarely far from the King, often standing just paces behind him to provide immediate protection. Currently, he also controls the King's cavalry force ( based in the capital, Dalreoch.

Iain Alpin's most significant and notorious action occurred in 774 at Caer Suibhne. During a private negotiation between the King and the Murchadh brothers - Domnhall and Fearchar - Alpin was the only other witness.

• The Official Version: The King asserted that the brothers attempted to assassinate him and that Iain Alpin’s “swift defence” saved his life, resulting in the deaths of both Murchadhs.
• The Murchadh version: According to a short account of the event, the “defence” was actually a premeditated execution. In this version, Alpin used a single swift motion to decapitate Earl Domnhall and then pivoted to drive his sword into Fearchar’s chest. To support the King's claim of treason, Alpin allegedly threw the brothers' swords onto the floor near their bodies to make it appear as though they had been drawn first. He then raised the alarm and escorted the wounded King to safety.

Whatever the truth, this event earned him the eternal enmity of Diarmid Murchadh, the current Earl of Uisdean, who views Alpin and the King as murderers who broke the sacred laws of hospitality.