What event occurred first out of ratification?

The first event that occurred out of ratification was the ratification of the United States Constitution itself, which took place on June 21, 1788, when New Hampshire became the ninth state to ratify it. This event established the Constitution as the foundational legal document of the United States, leading to the formal organization of the new government under its framework. Subsequently, the Bill of Rights was ratified in 1791, which further defined the rights of citizens.