Kyle Riker was a male Human from Alaska, North America, Earth, in the 24th century. He worked as a civilian strategic attaché to Starfleet, specializing in the frontier regions. He was well-known in his field throughout Starfleet, having a reputation for being "hard as nails" and "getting the job done."
Kyle Riker's only child, Starfleet officer William T. Riker, was born in 2335. Two years later, Kyle and William suffered a devastating loss when Kyle's wife Betty Riker died suddenly. This initial trauma created a rift between the two Rikers which lasted nearly thirty years.
The Rikers remained in Alaska at Betty's wish. The only thing which kept Kyle going was Will, but he did not feel as if he could discuss the situation with him, even when Will was older. The memories of Betty's presence at their Alaska home were also painful for both. (TNG: "The Icarus Factor") Never being able to know Betty while growing up, everything her son Will knew about her was taken from pictures and the stories Kyle told their son; stories Will begged his father to tell, over and over. In 2340, when Will was five years old and started school, he began to tell his new friends the same stories about his mother that his father told him, as if she was still alive. Eventually, he told the stories about her so often, he began to believe them, and that she had just gone away but was coming back. Soon, his teacher learned of this problem, and both she and Kyle had to talk to Will and make him realize that his mother was dead and she was not coming back. In his mind, that was the day his mother actually died. Will cried the entire night following, but later realized it was an important step in accepting his mother's death. (TNG: "Interface") Kyle hated cooking, and after Betty's death he left the duty to Will. (TNG: "Time Squared") Riker had a recipe for split pea soup, which his son Will enjoyed. (TNG: "The Outcast")
In 2344, the two went on a fishing trip. Will was able to hook a large fish, but Kyle insisted on reeling the fish in. This incident would bother Will for many years. Kyle and his son also played anbo-jyutsu occasionally. Kyle admitted that by the time Will was twelve, his skills were superior. Will did not learn until years later that the only reason he always lost was because his father used an illegal move called hachidan kiritsu.
In 2350, Kyle suffered an emotional breakdown and abandoned his son; they would not speak to one another again for another fifteen years. He later became involved with Doctor Katherine Pulaski, who said that she would have married him were it not for that Riker had "other priorities." (TNG: "The Icarus Factor", "Future Imperfect")
In 2353, Kyle was a civilian strategist advising Starfleet in its conflict with the Tholians at a starbase. The Tholians attacked the starbase, killing everyone except Kyle, who "alone had the will to endure, to face the pain, to live." After he recovered from his wounds, Kyle worked at Tokyo Base, where he helped work out the Fuurinkazan battle strategies. Then, he was asked to come to Starbase Montgomery, where he would work as a tactical advisor to Starfleet.
Kyle and his son were reunited in 2365 when Will, now first officer on the USS Enterprise-D, was offered command of the USS Aries and Kyle came aboard the Enterprise to brief Will on the Aries and its current mission. Though Will ultimately turned down command of the Aries, he and Kyle took the opportunity to finally settle their differences. (TNG: "The Icarus Factor")
In 2361 Kyle Riker was given another son when William Riker was duplicated in a transporter accident creating Thomas Riker, though no one was aware of his existence until 2369. Soon after learning of Thomas Riker's existence, William Riker noted that they should tell their father. (TNG: "Second Chances")