The Youngest President in American History

How An Assassination Thrust Theodore Roosevelt Into the White House at Age 42

The youngest president in American history was 42 years old when he entered the White House. The year was 1901, and the nation was still in shock. President William McKinley had been assassinated days earlier, and his young vice president, Theodore Roosevelt, ascended to the highest office in the land. 

"A terrible bereavement has befallen our people," Roosevelt wrote in a proclamation to the American people on Sept. 14 of that year. "The president of the United States has been struck down; a crime not only against the chief magistrate, but against every law-abiding and liberty-loving citizen."

Our youngest president was only seven years older than the constitution requirement that the White House occupant be at least 35 years old.

Roosevelt's leadership ability, though, defied his youthful age. "Though he remains the youngest person ever to hold America’s highest office, Roosevelt was one of the best prepared to be president, entering the White House with a broad understanding of governmental and legislative processes and with executive leadership experience," the Theodore Roosevelt Association states. 

Roosevelt was re-elected in 1904, at which time he reportedly said to his wife: "My dear, I am no longer a political accident."

All of our presidents have been at least 42 years old at the time they moved into the White House. Some of them have been decades older than that. The oldest president ever to take the White House, Donald Trump, was 70 when he took the oath of office. 

Who were the youngest presidents in U.S. history? 

Theodore Roosevelt
Theodore Roosevelt was 42 years old when he became president. Hulton Archive

Theodore Roosevelt was America's youngest president at 42 years old. He ascended to power following the assassination of President William McKinley in 1901.

At the time he took the oath of office, Roosevelt was 42 years, 10 months and 18 days old, according to 20th Century History expert Jennifer Rosenberg.

Interesting fact: Roosevelt had also been a state legislator in New York before working in Washington, D.C. He was elected to the statehouse at age 23, making him the youngest state lawmaker in New York at the time. More »

President John F. Kennedy
President John F. Kennedy. United States Congress

John F. Kennedy is often mentioned as the youngest president ever. He took the presidential Oath of Office in 1961 at age 43. 

While Kennedy isn't the youngest person to occupy the White House, he is the youngest person elected president. Keep in mind that Roosevelt wasn't initially elected president when he moved to the White House at age 42; he was vice president when McKinley was killed.

Kennedy was 43 years, 7 months and 22 days old when he took the oath. More »

President Bill Clinton
President Bill Clinton. The White House

Bill Clinton, a former governor of Arkansas, became the third-youngest president in U.S. history when he took the oath of office for the first of two terms in 1993. Clinton was 46 years old at the time.

A pair of Republicans interested in seeking the presidency in 2016, Ted Cruz and Marco Rubio, would replace Clinton as third-youngest president if elected.  More »

Ulysses Grant
Ulysses S. Grant was among the youngest U.S. presidents in history. Brady-Handy Photograph Collection (Library of Congress)

Ulysses S. Grant is the fourth-youngest president in U.S. history. He was 46 years, 10 months and five days old when he took the oath of office in 1869. 

Until Roosevelt's ascension to the presidency, Grant had been the youngest president to hold the office. He was inexperienced and his administration plagued by scandal. More »

Barack Obama
President Barack Obama is among the youngest presidents in U.S. history. Pool / Getty Images News

Barack Obama is the fifth-youngest president in U.S. history. He was  47 years, 5 months and 16 days old when he took the oath in 2009.

During the 2008 presidential race, his inexperience was a major issue; he had served only four years in the U.S. Senate before becoming president, and before that had served eight years as a state lawmaker in Illinois. More »