Neoclassicism was modeled on the ideals of ancient Greece and Rome and on Renaissance interpretations. It is often called Greek or Roman Revival.
Proportions, layout, components, and materials all are important elements in architecture. Notably, English and Continental influences that reached the colonies (the future United States) began to take hold, but the trend gained steam later in the 18th century and dominated the first half of the 19th century.
The conceptual ideals of the young republic, which drew on Rome as well, were thought to be reflected in the buildings, rendering the style suitable for the new nation.
The American variant known as "federal style" had its primary practitioner in Benjamin Latrobe (born in England). Thomas Jefferson's architectural talents, following Palladian models, shaped his plantation, Monticello, and the nearby University of Virginia campus.
Many public buildings such as capitols feature variants of one style with a prominent dome. Examples are the Virginia State Capitol (Thomas Jefferson) and later the U.S. Capitol (begun in 1793, several architects).