Isabel is the protagonist of The Portrait of a Lady. She is Mrs. Touchett’s niece. Her first appearance in Portrait is from Ralph’s perspective when she arrives at Gardencourt and is immediately characterized by her action of letting herself in and confidently picking up Ralph’s dog. He views her as having a “great deal of confidence, both in herself and others” (30), and Henry James therefore suggests her type as a modern American woman. From the outset, Isabel’s insistence on her liberty is her defining character trait. In her rejection of Caspar, she says, “I like my liberty too much. If there’s a thing in the world I’m fond of […] it’s my personal independence” (169).

Isabel loves knowledge and has a strong imagination. James describes her imagination as “ridiculously active; when the door was not open it jumped out of the window” (45). This description is important, as it characterizes Isabel’s focus on her own freedom, even within her mind. In addition, it is one of numerous architectural metaphors James uses to describe Isabel’s inner life. Despite her self-confidence, Isabel is very aware of what other people think of her. For example, she “liked to be thought clever, but she hated to be thought bookish; she used to read in secret and, though her memory was excellent, to abstain from showy reference” (47).