"The American Constitution: It's Origins and Development" (Seventh edition, Vol. 1) by Alfred H. Kelly, Winfred A. Harbison, and Herman Belz

Nothing like getting your information straight from the horse's mouth, as it were. Published in 1991, this edition of what was the standard textbook on American constitutional history at the time makes reference to people and events that may no longer be relevant, but what is still quite relevant is the text of the U.S. Constitution itself. Only one amendment -- the 27th, passed in 1992, is missing. (That's the one that says if Congress votes itself a pay raise, it won't take effect until after the next congressional election. Funnily enough, that amendment was originally proposed in 1789, but was lost for nearly 200 years when a college student found it and launched a campaign to get it ratified.)Of course, the history behind the creation of that unique document is still quite relevant, especially to legal and historical scholars, and anyone who went to the Law School of Facebook.