- "Did you realize you have a name? That's another thing you don't get to choose on Barrayar. Second son—that's you, my twin-six-years-delayed—gets the second names of his maternal and paternal grandfathers, just as the first son gets stuck with their first names. That makes you Mark Pierre. Sorry about the Pierre. Grandfather always hated it. You are Lord Mark Pierre Vorkosigan, in your own right, on Barrayar."
- ―Miles Vorkosigan[src]
Lord Mark Pierre Vorkosigan (pee-EHR vor-KO-suh-g'n) was the clone brother of Miles Naismith Vorkosigan, over six years removed.
He was created in a plot by Ser Galen, a Komarran terrorist, to replace Miles and assassinate Miles' father Aral and Emperor Gregor Vorbarra, claim the Imperial Throne and foment chaos and revolution. Miles, under the heavy influence of his mother's Betan upbringing, refused to kill Mark or even hinder him, and only desired he come to Barrayar as a true Vorkosigan. Mark, after he killed Ser Galen (who had become both his tormentor and father-figure) refused, and went his own way.
The prodigal son
- "I am too a Vorkosigan. The one who was trained as a deep-penetration mole and assassin. It really pisses me off when people underestimate me, y'know?"
- ―Mark to Baron Ryoval before killing him[src]
After a few years, Mark resurfaced and infiltrated the Dendarii Free Mercenary Fleet by posing as Admiral Miles Naismith, to send them on a mission to liberate more than 40 clones who were scheduled for body harvesting. The scheme was only semi-successful, as the clones were rescued, but Miles was killed by a needle grenade. While Miles' body was missing and in stasis in cryogenic freeze, Mark was returned to Barrayar; he learned there that he actually was Count Vorkosigan's heir if Miles died - as well as an Imperial heir to Emperor Gregor's throne. This was not much to his wishes, and as the search for Miles's body continued unsuccessfully, Mark convinced Countess Vorkosigan to allow him to mount a rescue mission - to Illyan's dismay - for Miles. Mark was captured by Baron Ryoval, who subjected him to physical, sexual and mental torture, during which Mark developed a disassociative disorder that he later dubbed "The Black Gang," a group of specialist subpersonalities:
Grunt expressed Mark's sexuality. He originated from Galen's sexual abuse of Mark, but Ryoval trained Grunt towards his own ideas of what Mark should desire. Over time and with the aid of a Betan therapist, Mark was able to translate Grunt's desires into more healthy relations. He was the first of Mark's subpersonas to be treated successfully.
Gorge expressed Mark's tendencies towards gluttony. His origins dated to Galen's habits of starving Mark to force him to become as thin as Miles naturally was. Mark's rebellion to this treatment took the form of overeating under stress; Ryoval turned this tendency to an extreme form. Over time, and with the aid of his Betan therapist, Mark eventually learned to transform Gorge's desires into a preference for gourmet eating. This was complicated at first by Howl's interference, but was eventually successfully resolved.
Howl expressed Mark's tendencies towards masochism. He likewise originated from Galen's abuse of Mark during training to act like Miles, and was likewise perverted by Ryoval. It is not known how Howl's preferences were redirected or translated by his therapist. Kareen, Mark's lover, made it known to Mark that she didn't care to deal with Howl.
Killer expressed Mark's assassin personality. Galen created Killer when he ordered Mark to kill Miles and Duv Galeni (even if it was Galen who died in their place). Mark's therapist wasn't too happy about Killer, but Kareen wasn't much troubled by him - likely Killer was allowed to remain as-is, since he was recognized by all the sub-personas as being the one among them who was closest to Mark himself.
Using his split personality, he was able to overpower and kill the Baron despite many injuries. Mark went on to sell 90% of Ryoval's assets to the Baron's rival and half-brother, Fell. In exchange, he received a healthy cut of Ryoval's estate and a bioresearch firm that Mark subsidized to combat the "clone chop shops" of Jackson's Whole. He also attracted the attentions of Kareen Koudelka, the youngest daughter of Count and Countess Vorkosigan's closest family friends.
Living as a Vorkosigan
To distinguish himself from Miles, Mark allowed himself to gain a large amount of weight. At times of stress, he tended to obesity. Unlike Miles, Mark was deadly in unarmed combat, having been trained as an assassin. Even at the low end of his preferred weight, he was described as "like a small tank"; he had a larger and more solid bone structure than his brother.
His romance with Kareen deepened while they were both studying at Beta Colony. Unfortunately, his relationship became strained upon their return to Barrayar when Kareen's parents learned of their sexual relationship at Miles' famously disastrous dinner party. Countess Vorkosigan ultimately stepped in and brokered an arrangement for them. During this time, Mark invested in a business deal with Escobaran scientist Enrique Borgos, who had created a new insect livestock he called butter bugs. Initially grotesque, if highly functional, Ekaterin Vorsoisson's design changes made the newly renamed "Glorious Bugs" highly popular.
Mark's legal status was complicated by a question of which set of laws could be applied to his situation. There was no Barrayaran tradition or law regarding clones, but as several characters observed during the Saga, "anything done twice on Barrayar is a tradition." Mark was pushed out into Vor society as Miles' brother and, at first, potential heir to the title of Count Vorkosigan. Other Vor might try to challenge this, if they dared. Under the laws of Beta Colony, the birthplace of Cordelia Naismith Vorkosigan, Mark could have been considered Cordelia's son, Miles's son, or the son of Ser Galen, depending on how the circumstances of his creation were interpreted. Mark tends to view Cordelia and Aral as his parents, with Miles as a sibling.
Mark's official title was Lord Mark, as he was not a direct heir to the Countship. Mark also viewed himself as a Jacksonian by birth, despite being an adopted Barrayaran.