No official list of supervisors in office prior to 1906 exists as the 1906 San Francisco earthquake destroyed all Board of Supervisors records . However , the names of San Francisco supervisors are recorded in many documents and newspapers from the time . The San Francisco Common Council was the predecessor of the San Francisco Board of Supervisors . The Common Council was made up of the Board of Aldermen and the Board of Assistant Aldermen , each composed of one member elected from each of the city 's eight wards . The first elections to these posts took place on May 1 , 1850 ( the same day as the vote on the city charter ) , and the Common Council took office on May 6 , 1850 . The Common Council had authority only within the city limits , which stretched west to Divisadero and Castro streets and south to 20th Street
1906 San Francisco earthquake
1906 San Francisco earthquake
Members of the San Francisco Board of Supervisors