Christopher Columbus — Cropped from photo (by historian Manuel Rosa) of the painting "The Virgin of the Navigators", 1531–36 by Alejo Fernández (1475-1545) - Photo .
Photo Credit: By Alejo Fernández (1475-1545) - Photo by historian Manuel Rosa., Public Domain, https://commons.wikimedia.org/w/index.php?curid=551286

Thomas Jefferson 1786 — Portrait of Thomas Jefferson while in London in 1786 by Mather Brown
Photo Credit: By 0AH-YSsKF68M1Q at Google Cultural Institute maximum zoom level, Public Domain, https://commons.wikimedia.org/w/index.php?curid=21870366

Andrew Jackson — Engraving of Jackson from the $20 bill Federal Reserve Note. Issue 2006
Photo Credit: a work of the United States government, is ineligible for US copyright, and is therefore in the public domain in the United States.

Jackson as president —
Photo Credit: By The Bureau of Engraving and Printing - Restoration by Godot13, Public Domain, https://commons.wikimedia.org/w/index.php?curid=33962951

Franklin Delano Roosevelt, 1933 —
Photo Credit: Public Domain Elias Goldensky (1868-1943) - This image is available from the United States Library of Congress's Prints and Photographs division under the digital ID cph.3c17121

John Wilkes Booth — Assassin of U.S. President Abraham Lincoln
Photo Credit: This image is available from the United States Library of Congress's Prints and Photographs division under the digital ID ppmsca.19233.

Emancipation Proclamation — The five page original document, held in the National Archives Building.
Photo Credit: By Lincoln, Abraham, 1809-1865, Public Domain, https://commons.wikimedia.org/w/index.php?curid=31578413

First Reading of the Emancipation Proclamation of President Lincoln — Shown from left to right are: Edwin M. Stanton, secretary of war (seated); Salmon P. Chase, secretary of the treasury (standing); Abraham Lincoln; Gideon Welles, secretary of the navy (seated); Caleb Blood Smith, secretary of the interior (standing); William H. Seward, secretary of state (seated); Montgomery Blair, postmaster general (standing); Edward Bates, attorney general (seated). Also shown are: Andrew Jackson, former president (painting centre); Simon Cameron, former secretary of war (painting left).
Photo Credit: By Francis Bicknell Carpenter - U.S. Senate: Art & History Home > First Reading of the Emancipation Proclamation by President Lincoln, Public Domain, https://commons.wikimedia.org/w/index.php?curid=507821

Lincoln Assasination — Shown in the presidential booth of Ford's Theatre, from left to right, are assassin John Wilkes Booth, Abraham Lincoln, Mary Todd Lincoln, Clara Harris, and Henry Rathbone
Photo Credit: By unattributed; based on the depiction from a mechanical glass slide by T. M. McAllister of New York, c1865-75 - Heritage Auctions, Public Domain, https://commons.wikimedia.org/w/index.php?curid=37937709

Sinking Spring — The spring that Sinking Spring Farm is named after.
Photo Credit: By Jpogi - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=57822356

Abraham Lincoln — Abraham Lincoln, the 16th president of the United States. Created: 8 November 1863
Photo Credit: Public Domain Alexander Gardner - This image is available from the United States Library of Congress's Prints and Photographs division under the digital ID cph.3a53289.