He was born in Englewood, New Jersey, and grew up in Rockport, Massachusetts. As a youth he worked on the local newspaper Gloucester Daily Times, covering school-boy sports, as well as town meetings and other civic affairs. He graduated from Columbia University in 1980, with a major in political science.
Baker is the author of the City of Fire trilogy, published by HarperCollins, which consists of the following historical novels: Dreamland (1998); the bestselling Paradise Alley (2002); and Strivers Row (2006). The middle volume of the trilogy won the 2003 James Fenimore Cooper Prize for Best Historical Fiction and the 2003 American Book Award. Paradise Alley was also chosen by bestselling Angela's Ashes author, Frank McCourt, as a Today show book club selection.
Baker's first book, Sometimes You See it Coming (1993), was a contemporary baseball novel loosely based on the life of Ty Cobb. He also wrote a graphic novel, Luna Park (2009), with drawings by Croatian artist Danijel Žeželj.
He was the chief historical researcher on Harold Evans’s illustrated history of the United States, The American Century (1998). He was a columnist ("In the News") for American Heritage magazine from 1998 to 2007. In 2009 appeared on C-SPAN's Washington Journal and The Colbert Report, to discuss the Obama presidency.
Baker is the author of America: The Story of Us (2010) and also wrote the new final chapter for the 2010 reissue of Baseball, the companion book to Ken Burns's 10-part film, Baseball, which aired on public television. He is also the co-author, with Yankees great, Reggie Jackson, of his memoir, Becoming Mr. October (2013).
In 2014, Baker's historical novel The Big Crowd was published by Houghton Mifflin Harcourt. Scott Turow for The New York Times Book Review wrote: "Delivers on what the title promises....I've read few other novels that portray, in such a nuanced way, the temptations of power, the complex division of control in a great metropolis and the perils of political deal-making in that environment.".
He is the author of the non-fiction title, America the Ingenious (2016), an exploration of great American inventions, published by Artisan books, an imprint of Workman Publishing.
A writer of over 200 newspaper and magazine articles, Baker was the recipient of a 2017 Guggenheim fellowship for non-fiction.
Baker resides in New York City, where he is a contributing editor to Harper's Magazine and a regular contributor to Politico.com, The New Republic, The New York Times, and The New York Times Book Review. His website address is: kevinbaker.info.