The Senate portico’s eastern front (facing the sunrise) is about America and its conquests. Frankly, the Capitol pediment pretty easy symbolism to decipher.
According to James M. Goode’s fine book “Washington Sculpture,” the woman in the middle is America standing on a rock. The sun rising at her feet as the enlightenment of progress. The woodsman is clearing a forest while an Indian seems to show despair that the whites are taking over his lands. On the left, a Revolutionary soldier with his hand on sword shows readiness. The merchant sitting on goods while touching a globe shows commerce and trade. The two boys are teacher show the future while the mechanic and his tools represent trade.
The marble pediment is 60 feet long and 12 feet high. It was sculpted by Thomas Crawford in 1863.