From his accent, James Delos was born in Scotland and was known to have been a "self-made" man by founding the company of Delos. He also had at least two children: Logan and Juliet. His children are American.
Was mentioned by William.
James Delos is first seen visiting Sweetwater early in the the park's history. With the Hosts, including Dolores Abernathy and Teddy Flood frozen around them, James and William have a conversation about the potential of the park. William tells him that if James can't see the potential for data-mining of the guests, then he is not as good a businessman as he has heard. James likes William's courage at challenging him, and invites him to tell him what kind of ideas he has in mind.
Later, James is at his retirement party, having seemingly passed over Logan for control of the company in favor of William. James mentions that he does not have much time left and coughs repeatedly, indicating that he is ill.