Monroe was born Norma Jeane Mortenson at the Los Angeles County Hospital on June 1, 1926 as the third child of Gladys Pearl Baker .

In early 1942, the company that employed Doc Goddard (a friend of her mother's husband, Grace McKee Goddard) relocated him to West Virginia.California child protection laws prevented the Goddards from taking Monroe out of state, and she faced the possibility of having to return to the orphanage.As a solution, she married their neighbors' 21-year-old son, a factory worker James "Jim" Dougherty; the wedding took place on June 19, 1942, just after her 16th birthday.

Monroe signed a contract with an acting agency in June 1946. After an unsuccessful interview at Paramount Pictures, she was given a screen-test by Ben Lyon, a 20th Century-Fox executive. Head executive Darryl F. Zanuck was unenthusiastic about it, but he was persuaded to give her a standard six-month contract to avoid her being signed by rival studio RKO Pictures, and Monroe's contract began in August. On July 23, 1946 she signed a contract with Twentieth Century-Fox Studios. (POF)

In September 1946, she divorced Dougherty, who was against her having a career.

She was given her first film role, bit parts in Dangerous Years (1947).

She became a friend and occasional sex partner of Fox executive Joseph M. Schenck, who persuaded his friend Harry Cohn, the head executive of Columbia Pictures, to sign her in March 1948.

Her only film at the studio (Columbia Pictures) was the low-budget musical Ladies of the Chorus (1948), in which she had her first starring role as a chorus girl who is courted by a wealthy man, but her contract was not renewed in September 1948. Ladies of the Chorus was released the following month but was not a success.

In December 1950, Hyde was able to negotiate a seven-year contract for Monroe with 20th Century-Fox. Marilyn Monroe Signed 20th Century Fox Contract in April 11, 1951.

When she refused to begin shooting yet another musical comedy, a film version of The Girl in Pink Tights, which was to co-star Frank Sinatra, the studio suspended her on January 4, 1954, but she reached a settlement with the studio in March: it included a new contract to be made later in the year

On January 14, she and Joe DiMaggio, whose relationship had been subjected to constant media attention since 1952, were married at San Francisco City Hall. They then traveled to Japan, combining a honeymoon with his business trip.

The publicity stunt (for the The movie "Seven Year Itch") placed Monroe on international front pages, and it also marked the end of her marriage to DiMaggio, who was furious about the stunt. The union had been troubled from the start by his jealousy and controlling attitude; Spoto and Banner have also alleged that he was physically abusive. After Monroe returned to Hollywood, she hired high-profile attorney Jerry Giesler and announced in October 1954 that she was filing for divorce from DiMaggio after only nine months of marriage.

Monroe began a new battle for control over her career and left Hollywood for the East Coast, where she and photographer Milton Greene founded their own production company, Marilyn Monroe Productions (MMP) – an action that has later been called "instrumental" in the collapse of the studio system. Announcing its foundation in a press conference in January 1955, Monroe stated that she was "tired of the same old sex roles. I want to do better things

Monroe and Miller were married in a civil ceremony at the Westchester County Court in White Plains, New York, on June 29, and two days later had a Jewish ceremony at the Waccabuc, New York home of Kay Brown, who was Miller's literary agent.

Monroe and Miller separated , and she was granted a quick divorce in Mexico in January 1961.

On May 19, she took a break to sing "Happy Birthday, Mr. President" on stage at President John F. Kennedy's early birthday celebration at Madison Square Garden in New York. She drew attention with her costume: a beige, skintight dress covered in rhinestones, which made her appear nude. Monroe's trip to New York caused even more irritation for Fox executives, who had wanted her to cancel it.

When Monroe was again on sick leave for several days, Fox decided that it could not afford to have another film running behind schedule when it was already struggling to cover the rising costs of Cleopatra (1963). On June 7, Fox fired Monroe and sued her for $750,000 in damages.Fox soon regretted its decision and re-opened negotiations with Monroe later in June.

During the final months of her life, Monroe lived at 12305 Fifth Helena Drive in the Brentwood neighborhood of Los Angeles. Her housekeeper Eunice Murray was staying overnight at the home on the evening of Saturday, August 4, 1962.Murray awoke at 3:00 a.m. on August 5 and sensed that something was wrong. Although she saw light from under Monroe's bedroom door, she was unable to get a response and found the door locked. Murray then called Monroe's psychiatrist, Dr. Ralph Greenson, who arrived at the house shortly after and broke into the bedroom through a window, finding Monroe dead in her bed. Monroe's physician, Dr. Hyman Engelberg, arrived at the house at around 3:50 a.m.and pronounced her dead at the scene. At 4:25 a.m., they notified the Los Angeles Police Department. At last they later discovered that Monroe died between 8:30 p.m. and 10:30 p.m. on August 4,and the toxicology report revealed that the cause of death was acute barbiturate poisoning.