Seamus O'Riley is a man of many names. His most common nickname is Ironhand, a name he earned during his time with the SDF Marine Corps after punching an insurgent to death using his right hand.
Seamus was the youngest of three brothers. As a child he spent most of his days playing soccer and (eventually) gravball once he could afford a basic rudimentary gravsuit.
With poor grades and barely any education to speak of due to him skipping school things looked grim for Seamus untill a marine sergeant inside a recuitment booth asked him if he wanted to see the world.
Thinking that it sounded like a good deal, Seamus accepted and managed to enroll with the SDFs military academy providing him with the neccessary grades needed to become a marine.
Seamus didn't consider himself to be better then others. He knew that there were better people out there. Smarter people. Nicer people. Faster people. Etc. But when it came to endurance and strength? That was Seamus' speciality.
Despite not having an actual plan for his career Seamus managed to climb the ranks simply by being one of the toughest and meanest marines Sol had ever seen since the Unification.
It didn't matter that Sol wasn't at war; there were plenty of pirates and renegade militants trying to mess with Seamus and his squad. They'd be sorry.
After a series of messy post-action reports, broken bones, gunshot wounds and angry letter written by his fellow soldiers and sent to his superiors Seamus was still going against all odds.
The name Ironhand soon replaced his own name. His new title was lined with fear and only uttered in whispers. It made SDF recruits widen their eyes and it forced pirates to always look over the shoulder whenever they were near Sol territory. Ironhand was equally hated as he was praised by his fellow soldiers.
As an OMS trooper Seamus continued to build up his reputation. He was mean. He was a walking tank. He was Sols rabid bulldog. In fact he was so mean that the SSOID begged him to join one of their Strikeforce units.
When the Sol-USR war broke out Seamus just smiled. For the first time in his career he was going up against something better than pirates: actual soldiers. Finally he got to use a bit of strategy. He already perfected the art of killing people. Now he had perfected the art of strategy.
Eventually Seamus was promoted to intelligence officer. It was a welcome change to overview the battlefield rather than sit knee-deep in the mud. At the end of the war he had executed hundreds of successfull operations, something which caught the attention of Talwin Williams.
After the war the SSG felt that it was time to change up the government. The conflict had postponed elections for a new high councilor and a new administrator. While the new players were sworn in Talwin Williams remained, he made sure that everything fell into place.
Two years later he was satisfied and resigned. Director O'Riley took over his office and now, while Sol tends to itself, the Ironhand remains vigilant.