The Cardinal of the Kremlin is part of a series of novels linked by the continuing character Jack Ryan: The Hunt for Red October (1984; see separate entry); Patriot Games (1987; see separate entry); Clear and Present Danger (1989; see separate entry); The Sum of All Fears (1991); Debt of Honor (1994); and Executive Orders (1996; see separate entry). These are sometimes referred to as the "Jack Ryan series." The Cardinal of the Kremlin and the later Ryan novels are linked by the continuing character John Clark to Without Remorse, 1993.

Clark returns as the featured character in the 1998 publication of Rainbow Six.

The Cardinal of the Kremlin also features other continuing characters such as the CIA officers Admiral Greer, Judge Moore, and Bob Ritter. The submarine captain Bart Mancuso, now nearing the end of his tour of duty aboard his ship, appears to ferry an operative named Clark to the Baltic shore...