Some of the most important primary source documents in American history are inaugural addresses. From 1789 to the present, presidents have used the inaugural address to outline their agendas, state their priorities, and provide a vision of how they intend to govern. As the presidency of Barack Obama begins, we have highlighted these five influential inaugural addresses in U.S. history:

George Washington's first inaugural address (1789).  With the country in post-Revolution chaos, Washington is called out of retirement by friends and colleagues and becomes the unanimous choice as the country's first president. He asks his fellow citizens to excuse errors due to his "incapacity as well as disinclination for the weighty and untried cares before me."

Thomas Jefferson's first inaugural address (1801).  Given a fter a bitter campaign against President John Adams, Jefferson's address calls for unity rather than retaliation against his opponents—a change in direction from the previous administration.  He pledges to allow dissenting voices and reminds them of their common ground: "We are all Republicans, we are all Federalists."

Abraham Lincoln's second inaugural address (1865).  At a mere 703 words, Lincoln's second inaugural address defines the meaning of the Civil War and approaches the task of Reconstruction "with malice toward none; with charity for all." Lincoln appeals to his fellow citizens "to bind up the nation's wounds," thus adopting a generous tone in an address now considered to be one of the fundamental documents in American history.

Franklin D. Roosevelt's first inaugural address (1933). With the United States in the midst of the Great Depression and the American economy hitting rock bottom the very month Roosevelt took office, Roosevelt's first inaugural address takes a markedly different tone than his predecessor Herbert Hoover's. Roosevelt takes the business community to task for incompetent and unethical practices that led to economic disaster. While he emphasizes that "the people of the United States have not failed," he assumes the role of the leader they elected to restore a sense of "discipline and direction."

John F. Kennedy's inaugural address (1961). In his brief address, Kennedy succinctly calls upon Americans to help achieve the New Frontier—a metaphor for Americans' "unfulfilled hopes and dreams" that Kennedy turned into a wide-ranging domestic program—through sacrifice and service and to take up the "burdens" of freedom.

Other notable inaugural addresses:

• Abraham Lincoln's First Inaugural Address (1861)
• Jefferson Davis's Inaugural Address to the Confederacy (1861)
• Rutherford B. Hayes's Inaugural Address (1877)
• Barack Obama's Inaugural Address (2009)