In 2269, this image of Abraham Lincoln was created by the Excalbians in a plot devised to better understand the concepts of good and evil, with Lincoln, Surak, James T. Kirk and Spock representing "good". It was Spock, who later observed that the Excalbian created Lincoln was created, and registered as humanoid, despite being a product of matter-energy conversion, whereby other Excalbians themselves were used as the source matter.
Lincoln was a personal hero of James T. Kirk, and this fact was the reason why the Excalbians created this image. The image of Lincoln first appeared sitting in a chair, floating in space above Excalbia. (TOS: "The Savage Curtain")
Though "Lincoln" was obviously an illusion created from Kirk's mind and the Enterprise memory banks, Kirk insisted on greeting Lincoln with full Presidential honors upon his boarding the Enterprise.
In the initial conflict forced by the Excalbians, the middle-aged simulacrum of Lincoln was able to hold his own against the forces of "evil", forcing Kahless the Unforgettable and Genghis Khan into retreat. The simulated Lincoln recognized a kindred spirit in the re-created image of the Vulcan patriarch, Surak, and sacrificed his "life" in an effort to save his counterpart.
Abraham Lincoln (Excalbian) appears in:
In "The Savage Curtain", Lincoln was portrayed by actor Lee Bergere.
Early planning had Mark Lenard in the role. He was eager to take the part, inspired by having played two well-received roles on Star Trek, but he ultimately couldn't accept it due to prior commitments to another TV series. "The Lincoln segment came up about Christmas time when we had a slight hiatus, and I thought I could work it in," he recalled, "But it turned out we just couldn't work it in. I think we went back to work on the other series too soon, and instead of having the six or seven days I would have needed to do the role, I only had three or four days." (Starlog #42, January 1981, p. 24)
The Excalbian Lincoln returns as part of the tenth anniversary of Star Trek Online. In the two-part mission "The Measure of Morality", the player character is brought to Excalbia, and Lincoln helps Yarnek oversee new "trials" to determine good and evil. When the trials go awry, Lincoln joins the player and Seven of Nine in protecting Yarnek from attackers. Following the conclusion of the trials, Lincoln volunteers to act as an Excalbian ambassador to the Alliance.