The anti-Federalists and their opposition to ratifying the Constitution were a powerful force in the origin of the Bill of Rights to protect Amercians' civil liberties. The anti-Federalists were chiefly concerned with too much power invested in the national government at the expense of states. (Howard Chandler Christy's interpretation of the signing of the Constitution, painted in 1940.)
The type of government system which best describes the relationship between member nations in the European Union, among the options – unitary system, confederation and federal system, is Option C – federal system.