PDF File Los Angeles : Structure of a City Government. Los Angeles was once the site of an Indian village, then of a Spanish colonial outpost and later a Mexican provincial capital. When Los Angeles was incorporated as an American city on April 4, 1850, it had a population of 1,610. There were no graded streets or sidewalks, no water system or lights and not a single public building. Sanitation and street lighting were simple. On Saturday mornings, residents cleaned up the streets in front of their own homes. Each owner whose house faced the street was required to put a light at the door in front of the house during the first two dark hours of every night.