The United States Congress passes the Chinese Exclusion Act.

The Chinese Exclusion Act was a United States federal law signed by President Chester A. Arthur on May 6, 1882, prohibiting all immigration of Chinese laborers. Building on the earlier Page Act of 1875, which banned Chinese women from migrating to the United States, the Chinese Exclusion Act was the only law ever implemented to prevent all members of a specific ethnic or national group from immigrating to the United States.Passage of the law was preceded by growing anti-Chinese sentiment and anti-Chinese violence, as well as various policies targeting Chinese migrants. The act followed the Angell Treaty of 1880, a set of revisions to the U.S.China Burlingame Treaty of 1868 that allowed the U.S. to suspend Chinese immigration. The act was initially intended to last for 10 years, but was renewed and strengthened in 1892 with the Geary Act and made permanent in 1902. These laws attempted to stop all Chinese immigration into the United States for ten years, with exceptions for diplomats, teachers, students, merchants, and travelers. They were widely evaded.The law remained in force until the passage of the Magnuson Act in 1943, which repealed the exclusion and allowed 105 Chinese immigrants to enter the United States each year. Chinese immigration later increased with the passage of the Immigration and Nationality Act of 1952, which abolished direct racial barriers, and later by the Immigration and Nationality Act of 1965, which abolished the National Origins Formula.

The United States Congress is the legislature of the federal government of the United States. It is bicameral, being composed of a lower body, the House of Representatives, and an upper body, the Senate. The Congress meets in the United States Capitol in Washington, D.C. Both senators and representatives are chosen through direct election, though vacancies in the Senate may be filled by a governor's appointment. Congress has 535 voting members: 100 senators and 435 representatives. The vice president of the United States has a vote in the Senate only when senators are evenly divided. The House of Representatives has six non-voting members.The sitting of a Congress is for a two-year term, at present, beginning every other January. Elections are held every even-numbered year on Election Day. The members of the House of Representatives are elected for the two-year term of a Congress. The Reapportionment Act of 1929 establishes that they be elected in single-member constituencies or districts by first-past-the-post and that Congressional districts be apportioned to states by population every ten years using the United States Census results, provided that each state has at least one Congressional representative. Each senator is elected at-large in their state for a six-year term, with terms staggered, so every two years approximately one-third of the Senate is up for election. Each state, regardless of population or size, has two senators, so currently, there are 100 senators for the 50 states.

Article One of the United States Constitution requires that members of Congress must be at least 25 years old (House) or at least 30 years old (Senate), have been a citizen of the United States for seven (House) or nine (Senate) years, and be an inhabitant of the state which they represent. Members in both chambers may stand for re-election an unlimited number of times.

The Congress was created by the Constitution of the United States and first met in 1789, replacing in its legislative function the Congress of the Confederation. Although not legally mandated, in practice since the 19th century, Congress members are typically affiliated with one of the two major parties, the Democratic Party or the Republican Party, and only rarely with a third party or independents affiliated with no party. In the case of the latter, the lack of affiliation with a political party does not mean that such members are unable to caucus with members of the political parties. Members can also switch parties at any time, although this is quite uncommon.