Jules Witcover identifies the best and worst veeps in US history in an interview about his new book

The office of the vice president has an underwhelming past. The country's founders saw it as a backstop measure. The VP would be a kind of president-in-waiting, should the president die or become disabled. But the founders concluded that the officeholder would be short on duties, or as one constitutional convention delegate noted "without employment." So they devised one extra role, to serve as the president of the Senate with just one task—cast the final tie-breaking vote.

In the early years of the young republic, the vice president was often the subject of lame jokes and ridicule, and with reason, says renowned political journalist Jules Witcover. The position, he writes, held "little significance or utility in governing the nation's affairs."

Witcover’s new encyclopedic volume The American Vice Presidency: From Irrelevance to Power, published by Smithsonian Books, traces the evolution of the office and features 47 biographical essays, one for each American vice president. Though many of them like Aaron Burr, Spiro Agnew, Adlai Stevenson or Nelson Rockefeller, are well-remembered for either notorious or distinguished careers, many others, like William R. King of Alabama and William A. Wheeler of New York, are now largely forgotten.

The author’s interviews with Walter Mondale, Al Gore, Joe Biden and Dick Cheney offer insightful commentary on the modern vice presidency. Says Biden: “The way the world has changed, the breadth and the scope of the responsibility an American president has virtually requires a vice president to handle serious assignments, just because the president’s plate is so very full.”

We asked Witcover to detail some of the backstories of the nation's vice presidents. to explain how the role of the vice president has changed, and to offer some advice for the next president in selecting the 48th...