Scholarly historical research continues to uncover surprising facts about our 16th president and the Civil War, the most recent discovery being that Abraham Lincoln, in addition to issuing the Emancipation Proclamation and favoring a funny beard and hat, spent much of his life killing vampires (at least according to the upcoming film). And you thought you knew your American history, huh? But seriously, there are more than a few examples of U.S. presidents who, while not known for hunting the undead, kicked ass in their time in their own unique ways. Here are seven of them. (Photo source: Kelly Bailey, licensed through Creative Commons)

1. Teddy Roosevelt: Bear Slayer

   As a child, Theodore Roosevelt suffered from recurring asthma attacks. He combated his asthma by exercising his body and exploring the untamed badlands of the United States, often alone and on horseback. During one of these adventures, a 9-foot, 1,200-pound grizzly bear appeared out of nowhere and reared up before him, ready to attack. Roosevelt, who hunted all of his life, kept his cool and shot the bear between the eyes. He later wrote, "The bullet hole in his skull was exactly between his eyes as if I had measured the distance with a carpenter's rule."

2. Andrew Jackson: Assassin Clubber

   Our seventh president, Andrew Jackson, in addition to championing states' rights, supported slavery and enforced the Indian Removal act. He also enjoyed a good duel, and happily killed a few of his opponents. In 1835, a deranged, unemployed house painter named Richard Lawrence attempted to shoot Jackson as he exited the Capitol building. Lawrence's first pistol misfired, as did a second he produced from his pocket. The 67-year-old Jackson responded by beating the crap out of Lawrence with his walking cane.

3. John F. Kennedy: Moon Shooter

   In his 1961 address before Congress, President John F. Kennedy threw down the gauntlet, demanding that funds be made available so that before the end of the decade, the U.S. could send a man to the moon and return him safely to Earth. Although he described this goal as a "race" against the much-feared Soviet Union, his overarching message was one of altruism. Kennedy declared, "We go into space because whatever mankind must undertake, free men must fully share."

4. Franklin D. Roosevelt: Axis Smasher

   Franklin D. Roosevelt's 1940 "Arsenal of Democracy" speech was a call to arm and support the Allies in Europe combating the Axis powers that included Germany, Italy, and Japan. Although Roosevelt indicated the United States would stay out of the actual fighting, the speech was carefully crafted as pure propaganda to prepare the country for war. A year after the speech, Japan would attack Pearl Harbor, but by then, Roosevelt and the country were ready to fight.

5. Harry S. Truman: Hell Raiser

   Harry S. Truman, our 33rd president, was popularly known as "Give 'em Hell, Harry" for his folksy, no-B.S. style of oration. Truman both inspired and later alienated his political brethren. He famously compared the job of a politician to that of a pianist in a whorehouse, concluding that the gig in the whorehouse was more honorable. When his daughter Margaret, a singer and writer, received a lukewarm review for one of her performances, Truman wrote the critic responsible a letter stating, "Someday, I hope to meet you. When that happens, you'll need a new nose, a lot of beefsteak for black eyes, and perhaps a supporter below!"

6. George Washington: Ice Breaker

   It was December 1776, a year into what would be known as the American Revolution, and it was obscenely cold. Fearing his troops were doomed to freeze to death unless they made a bold strategic move, Gen. George Washington and his men made the journey by boat, in freezing rain and sleet, through ice flows and rough water, across the Delaware river to attack a contingent of German soldiers hired by the British Empire. The resulting battle and Washington's decisive victory were a turning point in the American War of Independence.

7. Barack Obama: Dream Weaver

   With the next presidential election just on the horizon, it remains to be seen if President Barack Obama's power to conjure and invoke dreams will garner the support he needs to win the 2012 election. Back in 2008, after accepting the Democratic Party nomination, Obama, the country's first African-American major-party presidential nominee, delivered a speech that resonated with people who had been present years before for Martin Luther King's iconic "I Have a Dream" speech. Since then, many of Obama's supporters have expressed disappointment with his performance in office. But dreams die hard.