There have been several periods in America's history when the Union was sorely tried, the federal system put to extreme test. The First Congress met in such a time, as did the Seventy–third Congress, in 1933. The men of 1789 essayed a unique task; they had to vitalize structures visualized to that point in thought and discourse alone. Still, despite their magnitude, the dangers that the founding legislators confronted were also vague and unfocused. In 1933, on the other hand, the threat was clear; a devastating depression threatened to obliterate the economic security and pride of millions of Americans. Even so, most will agree that the Civil War provided the greatest challenge to the American Republic. The pledges of Union had been violated; one–time citizens were in arms against it; its very existence hung in the balance. How did the Congress of these years react to the crisis? Did its members willingly follow President Lincoln's lead? Did they find in their own system of internal governance the direction and will to contribute positively to the Union effort?

The Seventy–third Congress and those of the Civil War years, the Thirty–seventh and the Thirty–eighth, provide opportunities to study the American government under extreme stress. The Democratic majorities in Franklin Delano Roosevelt's first administration were so cowed by events, it has been said, that they accorded their president the famed one hundred days of grace when executive recommendations were treated with special deference. Apparently Lincoln experienced no such period of willing acquiescence.