The famous "Spirit of '76" painting, originally know as "Yankee Doodle" was painted in 1875 by Archibald MacNeal
Willard (1836 to 1918) for the Philadelphia Centennial Exposition of 1876.
Willard, a native to Ohio, fought during the Civil War as a soldier in the 86th Ohio Volunteer Infantry in 1863.
Willard's inspiration for the painting arose as he watched a parade march past him in the Town Square.  The center figure is most notable as it resembles Archibald's late father.
The original paining is on display in Abbot Hall in Marblehead, MA.
There are more that one painting of the "Spirit Of '76" produced by Willard, which are hung in various Government buildings.
Willard went on to paint several other scenes from the Civil War era.

Image: The Library Of Congress @ loc.gov
Digital file from the original print