“Do what you can with what you have where you are,” the robust and outspoken Theodore Roosevelt liked to say. And he lived it—charging through life as a rancher and sheriff in the Dakota Territory, as a writer of books and articles, and as a lieutenant colonel in the Spanish-American War, where his volunteer cavalry regiment of cowboys, polo players, and college athletes became famously known as the “Rough Riders.” Newspaper accounts of their exploits turned Roosevelt into a national hero and saddled him with a nickname he never liked: Teddy.

On September 6, 1901, President William McKinley was shot in Buffalo. Roosevelt—then vice president—was in Vermont at Lake Champlain, speaking at a game and fish event when he received word. He rushed back to Buffalo, but the doctors believed McKinley would recover, so Roosevelt continued on to the Adirondacks for a long-planned hiking trip. But on September 13, messengers reached him deep in the mountains with grim news: the president was dying. Roosevelt hurried down from Mount Marcy and rushed toward Buffalo, but McKinley died before he could arrive. That evening, at the house of his friend Ainsley Wilcox, the 42-year-old Roosevelt donned borrowed formal wear and took the oath of office—making “that damned cowboy,” in the words of party boss, Mark Hanna, the youngest president in American history.

As president for a new century, Roosevelt brought new energy and authority to the office. With his deep love for the outdoors, he became the nation’s first true environmentalist, setting aside millions of acres for forests, parks, and wildlife refuges. He pushed the United States more assertively onto the world stage, often citing his favorite proverb: “Speak softly and carry a big stick. You will go far.” At home, his Square Deal sought fair play for workers and consumers, ushering in landmark workplace and corporate reforms—so unsettling to financiers that J. P. Morgan is said to have prayed that a lion on Roosevelt’s upcoming African safari would “do its duty.”

Colorful, confident, and larger than life, Theodore Roosevelt is consistently ranked among America’s greatest presidents. He surely would have called such praise “bully!”—fitting for the man whose face now towers over the Black Hills on Mount Rushmore.

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