
When did Los Angeles become an American city
It was on the 4th of April 1850 when Ciudad de Los Angeles (City of Angels) became the City of Los Angeles. That was several months before California was admitted into the Union.
Los Angeles County was already established as one of the 27 original counties on February 8, 1850 and it derived its name from the area known as Los Angeles, which is already a large community and thus made it the designated seat of County government. The first governing body of Los Angeles County was a three-man Court of Sessions, elected by the people on April 1, 1850.
http://en.wikipedia.org/wiki/History_of_Los_Angeles#The_Transitional_Era_1848.E2.80.931870
http://content.cdlib.org/ark:/13030/hb4w1009kr/

