The Senate approved the Treaty of San Lorenzo (or Pinckney's Treaty), acquiring the land forming the future state of Alabama.
The Mississippi Territory was divided into the state of Mississippi and the Territory of Alabama.
Alabama became the 22nd state in the Union.
William R. King of Cahaba, Alabama's second U.S. senator, took his oath of office and was seated. Senators King and Walker then drew lots to determine their class assignments. King drew Class 2 with a term to expire March 3, 1823. Walker drew Class 3, with a term to expire March 3, 1825.
Senator Henry Clay of Kentucky apologized to Alabama senator William R. King. Following a dispute over Senate printers, King challenged Clay to a duel. When the two men began to prepare for an actual duel, the Senate's sergeant at arms arrested both men. A formal apology from Clay ended the dispute without bloodshed.
Senator William R. King was elected vice president of the United States on the Democratic ticket with Franklin Pierce. King was the first senator to gain a major party's nomination for the vice presidency. By special act of Congress, King was permitted to take the oath of office in Havana, Cuba, on March 4, 1853, where he was recovering from health problems. Returning to his home in Alabama, King died a month later, on April 18, 1853, without ever assuming his duties as vice president.
The Senate elected Benjamin Fitzpatrick of Wetumpka, who began his Senate service in 1848, as president pro tempore. Fitzpatrick served nine separate terms as president pro tempore between 1857 and 1860.
Clement C. Clay Jr. of Huntsville, who began his Senate service in 1853, became chairman of the Senate Committee on Commerce (today's Committee on Commerce, Science, and Transportation), a position he held from 1857 to 1861.
Alabama was allowed to resume representation in the U.S. Congress. On July 21, George E. Spencer of Decatur was elected, and on July 23, Willard Warner of Montgomery, was elected, becoming Alabama's first post-Civil War U.S. senators.
Congress accepted a statue of Jabez Lamar Monroe Curry, one of Alabama's two contributions to the National Statuary Hall Collection. The seven-foot-four-inch marble statue was designed by artist Dante Sodini. (The statue was replaced by one of Helen Keller in 2009.)
The Senate voted to deny a seat to Franklin P. Glass who had been appointed by Alabama governor Emmett O'Neal.
Frank S. White of Birmingham became Alabama’s first directly elected senator after ratification of the Seventeenth Amendment in 1913. He ran in a special election to fill the vacancy in the term ending March 3, 1915, caused by the death of Senator Joseph Johnston.
Oscar W. Underwood of Birmingham, who began his Senate service in 1915, was elected chairman of the Democratic Conference. Beginning in 1920, the Democratic Conference chairperson also served as Democratic floor leader. On April 27, 1920, Underwood became the first officially designated Democratic floor leader, a position he held until 1925.
John H. Bankhead II of Jasper took the oath of office as U.S. senator, becoming the third of four members of the Bankhead family to serve Alabama in the U.S. Congress. His father, John H. Bankhead, served in the Senate from 1907 to 1920. His brother, William B. Bankhead, had been serving in the House of Representatives since 1917.
J. Thomas "Cotton Tom" Heflin of Lafayette delivered his last blast in the Senate Chamber following his defeat as an independent candidate for the Senate in 1930. Heflin contested the election results and when the issue was debated by the full Senate, was allowed the unusual honor of speaking on his own behalf, even though he had been out of office for more than a month.
The Senate approved Alabama senator Hugo Black's resolution 349, to establish a special investigatory committee to inquire into the government's system of awarding of air and ocean mail contracts. Black was appointed chairman. The investigation lasted three years and led to passage of the Air Mail Act of 1934.
Hugo L. Black became chairman of the Senate Committee on Education and Labor (today's Committee on Health, Education, Labor, and Pensions).
Dixie Bibb Graves of Montgomery became the first woman to represent Alabama in the U.S. Senate. Appointed by her husband, Governor Bibb Graves, to fill a vacant seat, Graves served until January 10, 1938.
Senator John J. Sparkman of Huntsville ran unsuccessfully for vice president of the United States on the Democratic ticket with presidential candidate Adlai Stevenson of Illinois. They lost to Dwight D. Eisenhower and Senator Richard M. Nixon.
J. Lister Hill became chairman of the Senate Committee on Labor and Public Welfare (today's Committee on Health, Education, Labor, and Pensions), a position he held from 1955 to 1969.
James B. Allen of Gadsden received the Golden Gavel Award for presiding over the Senate for 100 hours in a single session. On September 18, 1970, Senator Allen received a second Golden Gavel Award for presiding an additional 100 hours.
Senator John J. Sparkman became Alabama’s longest-serving senator, surpassing J. Lister Hill's record of 30 years, 11 months, and 24 days. Sparkman went on to serve a total of 32 years, 1 month, and 28 days.
Maryon P. Allen of Gadsden became the second woman to represent Alabama in the U.S. Senate. Appointed on June 8, 1978, to fill the vacancy caused by the death of her husband, Senator James B. Allen, she took her seat on June 12, 1978, and served until November 7, 1978.
With the Republican Party winning control of the House and Senate, Alabama senator Richard C. Shelby, a conservative Democrat who previously served in the House, switched to the Republican Party, taking advantage of his seniority in the Senate to gain the chairmanship of the Permanent Select Committee on Intelligence and keep his subcommittee chairmanships.
Senator Jefferson B. Sessions III of Mobile received the Golden Gavel Award for presiding over the Senate for 100 hours in a single session. Senator Sessions received a second Golden Gavel Award on October 25, 2000, for presiding an additional 100 hours.
Richard C. Shelby became chairman of the Senate Committee on Banking, Housing and Urban Affairs, a position he held from 2003 to 2007 and again starting in 2015.