Abraham Lincoln, 16th president, March 4, 1861 to April 15, 1865
Resources:
Abraham Lincoln Papers - a collection of over 20,000 Lincoln documents available online from the Library of Congress, American Memory website.
Selected Speeches and Writings by Abraham Lincoln
Election of 1860 and Civil War, Eagleton Institute of Politics, Rutgers University
Andrew Johnson, 17th president, April 15, 1865 to March 3, 1869
Ulyssses S. Grant, 18th president, March 4, 1869 to March 3, 1877