High Quality Content by WIKIPEDIA articles! The Federalist Era was a time period in American history from roughly 1789-1801 when the Federalist Party was dominant in American politics. This period saw the adoption of the United States Constitution and the expansion of the federal government. In addition, the era saw the growth of a strong nationalistic government under the control of the Federalist Party. Among the most important events of this period was the foreign entanglements between France and England, the assertion of a strong, centralized federal government, and creation of political parties.