LGBT Rights Milestones Fast Facts

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(CNN)Here is a look at lesbian, gay, bisexual and transgender milestones in the United States.

Timeline:
1924 - The Society for Human Rights is founded by Henry Gerber in Chicago. It is the first documented gay rights organization.
1950 - The Mattachine Society is formed by activist Harry Hay and is one of the first sustained gay rights groups in the United States. The Society focuses on social acceptance and other support for homosexuals.
April 1952 - The American Psychiatric Association's diagnostic manual lists homosexuality as a sociopathic personality disturbance.
    April 27, 1953 - President Dwight D. Eisenhower signs an executive order that bans homosexuals from working for the federal government, saying they are a security risk.
    September 1955 - The first known lesbian rights organization in the United States forms in San Francisco. Daughters of Bilitis (DOB). They host private social functions, fearing police raids, threats of violence and discrimination in bars and clubs.
    July 1961 - Illinois becomes the first state to decriminalize homosexuality by repealing their sodomy laws.
    September 11, 1961 - The first US-televised documentary about homosexuality airs on a local station in California.
    June 28, 1969 - Police raid the Stonewall Inn in New York City. Protests and demonstrations begin, and it later becomes known as the impetus for the gay civil rights movement in the United States.
    1969 - The "Los Angeles Advocate," founded in 1967, is renamed "The Advocate." It is considered the oldest continuing LGBT publication that began as a newsletter published by the activist group Personal Rights in Defense and Education (PRIDE).
    June 28, 1970 - Community members in New York City march through the local streets to recognize the one-year anniversary of the Stonewall riots. This event is named Christopher Street Liberation Day, and is now considered the first gay pride parade.
    1973 - Lambda Legal becomes the first legal organization established to fight for the equal rights of gays and lesbians. Lambda also becomes their own first client after being denied non-profit status; the New York Supreme Court eventually rules that Lambda Legal can exist as a non-profit.
    January 1, 1973 - Maryland becomes the first state to statutorily ban same-sex marriage.
    March 26, 1973 - First meeting of "Parents and Friends of Gays," which goes national as Parents, Families and Friends of Lesbians and Gays (PFLAG) in 1982.
    December 15, 1973 - By a vote of 5,854 to 3,810, the American Psychiatric Association removes homosexuality from its list of mental disorders in the DSM-II Diagnostic and Statistical Manual of Mental Disorders.
    1974 - Kathy Kozachenko becomes the first openly LGBT American elected to any public office when she wins a seat on the Ann Arbor, Michigan City Council.
    1974 - Elaine Noble is the first openly gay candidate elected to a state office when she is elected to the Massachusetts State legislature.
    January 14, 1975 - The first federal gay rights bill is introduced to address discrimination based on sexual orientation. The bill later goes to the Judiciary Committee but is never brought for consideration.
    March 1975 - Technical Sergeant Leonard P. Matlovich reveals his sexual orientation to his commanding officer and is forcibly discharged from the Air Force six months later. Matlovich is a Vietnam War veteran and was awarded both the Purple Heart and the Bronze Star. In 1980, the Court of Appeals rules that the dismissal was improper. Matlovich is awarded his back pay and a retroactive promotion.