Same-Sex Marriage Fast Facts

(CNN)Here's some background information about same-sex marriage in the United States and worldwide.

US Timeline:
September 21, 1996 - President Bill Clinton signs the Defense of Marriage Act banning federal recognition of same-sex marriage and defining marriage as "a legal union between one man and one woman as husband and wife."
    December 20, 1999 - The Vermont Supreme Court rules that gay and lesbian couples should be given the same rights as heterosexual couples.
    November 18, 2003 - The Massachusetts Supreme Court rules that a ban on same-sex marriage is unconstitutional.
    February 12-March 11, 2004 - Nearly 4,000 same-sex couples get marriage licenses in San Francisco, but the California Supreme Court eventually orders San Francisco to stop issuing marriage licenses. The nearly 4,000 sanctioned marriages are later nullified by the California Supreme Court.
    February 20, 2004 - Sandoval County, New Mexico issues 26 same-sex marriage licenses, but they are nullified by the state attorney general the same day.
    February 24, 2004 - President George W. Bush announces support for a federal constitutional amendment banning same-sex marriage.
    February 27, 2004 - New Paltz, New York Mayor Jason West performs same-sex marriages for about a dozen couples. In June, the Ulster County Supreme Court issues West a permanent injunction against marrying same-sex couples.
    March 3, 2004 - In Portland, Oregon, the Multnomah County Clerk's office issues marriage licenses for same-sex couples. Neighboring Benton County follows on March 24.
    July 14, 2004 - The US Senate blocks a proposed constitutional amendment to ban same-sex marriage from moving forward in Congress.
    September 30, 2004 - The US House of Representatives votes against amending the Constitution to prohibit same-sex marriage.
    October 5, 2004 - A Louisiana judge throws out an amendment to the state constitution banning same-sex marriage because the ban also includes civil unions. In 2005, the Louisiana State Supreme Court reinstates the constitutional amendment.
    November 2, 2004 - Eleven states pass constitutional amendments defining marriage as being between a man and a woman only: Arkansas, Georgia, Kentucky, Michigan, Mississippi, Montana, North Dakota, Ohio, Oklahoma, Oregon and Utah.
    March 14, 2005 - A Superior Court judge rules that California's law that limits marriage to a union between a man and a woman is unconstitutional.
    April 14, 2005 - Oregon's Supreme Court nullifies the same-sex marriage licenses issued there in 2004.
    May 12, 2005 - A federal judge strikes down Nebraska's ban on protection and recognition of same-sex couples.
    August 5, 2004 - A Washington judge rules the state's law defining marriage is unconstitutional.
    September 6, 2005 - The California Legislature passes a bill to legalize same-sex marriage. The legislature is the first in the United States to act without a court order to sanction same-sex marriages. California Governor Arnold Schwarzenegger later vetoes the bill.
    September 14, 2005 - The Massachusetts Legislature rejects a proposed amendment to its state constitution to ban same-sex marriages.
    October 7, 2005 - The Massachusetts Supreme Judicial Court hears a case challenging a 1913 law prohibiting nonresidents from marrying in Massachusetts if the marriage is prohibited in their home state. The law has been used in recent years to prevent same-sex couples from getting married.
    November 8, 2005 - Texas becomes the 19th state to adopt a constitutional amendment banning same-sex marriage.
    January 20, 2006 -