Pursuant to a resolution of the Congress of the Confederation in 1788, the first session of the First Congress under the Constitution convened 4 March 1789. Up to and including 20 May 1820, 18 acts were passed providing for the meeting of Congress on other days in the year. The first and second sessions of the First Congress were held in New York City.

Subsequently, Philadelphia was the meeting place through the first session of the Sixth Congress and, since then, Congress has met in Washington, D.C. The 20th Amendment to the Constitution, proclaimed as ratified 6 February 1933, established noon on the 3rd day of January as the meeting date, unless the Congress by law appoints a different day.

The Constitution states, in Article I, Section 4, that "The Congress shall assemble at least once in every Year, and such Meeting shall be on the first Monday in December, unless they shall by law appoint a different day." However, “[The President] may, on extraordinary Occasions, convene both Houses, or either of them...” according to Article 2, section 3, meaning if the President so chooses, Congress can return from a recess period to work on matters in an emergency or ‘special session.’ An example of a ‘Special Session’ of the House being called can be found with President Abraham Lincoln during the early years of the Civil War. Lincoln called Congress back into session on 4 July 1861 throughout 6 August 1861 to discuss war measures.

Traditionally, there have been periods of time where Congress adjourned throughout the month of August as far back as the second session of the First Congress in 1790. The first period of time that Congress adjourned in the month of August was 12 August 1790 until the beginning of the third session of the First Congress on 6 December 1790.

The Speaker of the House works with House Leadership on deciding the calendar for the Congressional Year. In the 19th century, Congress adjourned in June or July and would not sit in August, although on a few occasions it did meet in August. One reason for this late summer recess was the extreme heat and humidity. After 1911, the House frequently met throughout the summer, including in August, adjourning in the fall. During World War II, Congress was in almost continual session, a practice that continued on and off into the 1960s.

In 1970, Congress formalized an “August Recess.” In section 132(a) of the Legislative Reorganization Act of 1970 provides as follows:

Unless otherwise provided by the Congress, the two Houses shall—

1. Adjourn sine die not later than July 31 of each year; or (2) in the case of an odd-numbered year, provide, not later than July 31 of such year, by concurrent resolution adopted in each House by roll call vote, for the adjournment of the two Houses from that Friday in August which occurs at least thirty days before the first Monday in September (Labor Day) of such year to the second day after Labor Day.
   
2. This section shall not be applicable in any year if on July 31 of such year a state of war exists pursuant to a declaration of war by the Congress.

Since that time, Congress has occasionally met in August, as sometimes the session continued into the first couple of days. The last time Congress met for most of the month of August was in 1994, when Congress was in session from July 13 to August 26, just breaking for two weeks for Labor Day.