Final answer:
The first actions taken by Congress included structuring the federal government, establishing departments, and enacting the Judiciary Act and the 1789 Tariff Act to support a powerful national government.
Step-by-step explanation:
The first action taken by Congress, after the United States Constitution was adopted and the new government was formed, encompassed various significant legislative steps. Initially, Congress focused on structuring the federal government by establishing departments, including naming the first attorney general. One of the first major legislative actions was the passing of the Judiciary Act in July 1789, which created a Supreme Court with six justices, showcasing their commitment to a strong national government. Additionally, the first major piece of economic legislation was the enactment of the 1789 Tariff Act, which was aimed at raising revenue to resolve economic challenges and was seen as a victory for nationalists who favored a robust federal government.
Before these legislative actions, even before the first drafting of the Olive Branch Petition, Congress had taken measures to prepare for war, such as establishing the Continental Army and appointing George Washington as commander-in-chief in June 1775. Such preparations were also among the early actions taken by the delegates.