Answer by taking a quote from the following article:

Born Florence Annie Bridgwood in Hamilton, Ontario, she was youngest of three children of George Bridgwood, an English-born carriage builder and Charlotte "Lotta" Bridgwood (nee Dunn), a vaudeville actress. Charlotte Bridgwood had emigrated to Canada from Ireland after the Great Famine with her family as a child. She was known professionally as Lotta Lawrence and was the leading lady and director of the Lawrence Dramatic Company. At the age of three, Lawrence made her debut onstage with her mother in a song and dance routine.

Finding themselves "at liberty," Lawrence and Solter in 1909 were able to join the Independent Moving Pictures Company of America (IMP). The company, founded by Carl Laemmle, the owner of a film exchange (who later absorbed IMP into Universal Pictures, which he also founded and also the president), was looking for experienced filmmakers and actors. Needing a star, he lured Lawrence away from Biograph by promising to give her a marquee. First, Laemmle organized a publicity stunt by starting a rumor that Lawrence had been killed by a street car in New York City. Then, after gaining much media attention, he placed ads in the newspapers that announced, "We nail a lie", and included a photo of Lawrence. The ad declared she is alive and well and making The Broken Oath, a new movie for his IMP Film Company to be directed by Solter.  Laemmle had Lawrence make a personal appearance in St. Louis, Missouri in March 1910 with her leading man to show her fans that she was very much alive, making her one of the first performers not already famous in another medium to be identified by name by her studio.  Laemmle generated attention by falsely claiming that Lawrence's St. Louis fans were so excited to learn that she had not died that they rushed her in a frenzy and tore her clothes off. Partially due to Laemmle's ingenuity, the "star system" was born and before long, Florence Lawrence became a household name. However, her fame also proved that the studio executives who had concerns over wage demands soon had their fears proved correct. Laemmle managed to lure William Ranous, one of Vitagraph's best directors, over to IMP. Ranous introduced Laemmle to Lawrence and Solter, and they began to work together. Lawrence and Solter worked for IMP for eleven months, making fifty films. After this, they went on vacation in Europe.  When they returned to the United States, they joined a film company headed by Siegmund Lubin, described as the "wisest and most democratic film producer in history". She once again teamed with Arthur Johnson, and the pair made 48 films together under Lubin's direction. At the time, the film industry was controlled by the Motion Picture Patents Company (MPPC), a trust formed by the major film companies. IMP was not a member of the MPPC, and hence operated outside its distribution system. Theaters found showing IMP films lost the right to screen MPPC films. IMP, therefore, had powerful enemies in the film industry. It managed to survive largely due to Lawrence's popularity.

Did she demand higher wages?
Laemmle managed to lure William Ranous, one of Vitagraph's best directors, over to IMP. Ranous introduced Laemmle to Lawrence and Solter, and they began to work together.