Abraham Lincoln and His Second Son Tad. Photographed by Alexander Gardner (American, born Scotland, 1821 - 1882) on April 9, 1865. Albumen silver print. Abraham Lincoln (February 12, 1809 - April 15, 1865) was the 16th President of the United States, from March 1861 until his assassination in 1865. He led his country through the American Civil War, preserving the Union, ending slavery, and promoting economic and financial modernization. Lincoln married Mary Todd in 1842. They had four sons: Robert Todd, Edward Baker, Willie and Tad, but only Robert survived to adulthood.