What federal government law or actions was in question in the NcCulloch v. Maryland (1819) case?

It's not NcCulloch. It's McCulloch.





And here is your answer to McCulloch v Maryland - it was a landmark decision by the Supreme Court of the United States. The State of Maryland had attempted to impede operation of a branch of the Second Bank of the United States by imposing a tax on all notes of banks not chartered in Maryland. Though the law, by its language, was generally applicable, the U.S. Bank was the only out-of-state bank then existing in Maryland, and the law is generally recognized as having specifically targeted the U.S. Bank. The Court invoked the Necessary and Proper Clause in the Constitution, which allowed the Federal government to pass laws not expressly provided for in the Constitution's list of express powers as long as those laws are in useful furtherance of the express powers.





This fundamental case established the following two principles:





1. The Constitution grants to Congress implied powers for implementing the Constitution's express powers, in order to create a functional national government.





2. State action may not impede valid constitutional exercises of power by the Federal government.