A dynamic and curious 14-year-old girl living in Brooklyn, whose personal quest to learn more about her family's history intertwines with the central plot of the novel.

A friend of Leopold Gursky who grew up with aspirations of being a writer and whose life took a complicated turn, leading to the publication of the book within the novel.

Alma Singer's younger brother, who is deeply religious and eccentric, believing he might be one of the lamed vovnik, tying his faith to his family origins and connection to heritage.

Leopold Gursky's best friend from Poland, whose improbable reunion with Leo in New York sustains his spirit amid his solitude.

Alma and Bird's mother, who is a translator struggling with grief and depression following the death of her husband, using language and literature as a refuge.

The deceased father of Alma and Bird, whose legacy and connection to The History of Love remain significant influences on the characters' lives and actions.

Leo's first love from Poland, whose name and memory become central to the unfolding of events and exploration of love throughout the novel.

A Russian teenager and Alma Singer's only close friend, with whom she shares a meaningful letter-writing relationship before meeting in person.