Martice was the Sovereign of the Talthuns going to Ardena. His body was killed when the ship crash-landed on P2A-347. His mind went on living inside the mind of Dr. Daniel Jackson but was later purged from that mind. As sovereign, Martice apparently had absolute power over the rest of his people, which made him rather arrogant, with Dr. Janet Fraiser commenting that he was almost as arrogant as a Goa'uld. During his time in Daniel's body, he appeared more concerned about whether his people were concerned for him than whether they were all right themselves, initially expressing anger at his new appearance before he learned what had happened to his original body. He attempted to order Pharrin, the engineer responsible for the transference, to purge all minds but his from Daniel's body, but Colonel Jack O'Neill overrode that order, stating that Martice was dead and had no right to remain in Daniel's body any longer. (SG1: "Lifeboat")
As the self-confessed leader or Sovereign of his people, Martice was extremely arrogant, believing that his people would support him regardless of what happens while remaining unaware of the fact that they are probably dead.