Click on the chart to enlarge.
Los Angeles County was a much different place in 1939. It was still one of the most fruitful agricultural counties in the United States, with the west's largest stock yards, orchards, ranches and dairies all over the place. The county had fewer than 2.8 million people, less than a third of today's population. A slower and simpler place, as this 1939 organizational chart of county government reflects in the titles of departments and top officials. There's the Farm Advisor, the Livestock Inspector, the Superintendent of Charities and the Director of Crossing Guards.
Perusing the chart, you can see that today's Registrar-Recorder/County Clerk used to be three separate departments: the Registrar of Voters, Recorder, and County Clerk. The old functions of Road Commissioner, County Surveyor, County Engineer and Chief Mechanical Engineer now all fall under one Public Works Department.
One department that remains today as it was in 1939 is the Public Defender — the first office of its kind in the nation, started by the Board of Supervisors in 1914. The org chart was put up on Twitter this week by the office of the county chief executive officer, which in 1939 was still known as the Chief Administrative Officer.
*Jan. 7 Update: We now have a source, per Edward Sumcad of the county. He says the chart appears in a book, “The Courthouse Crowd,” written by Tom Sitton, the curator emeritus of the Natural History Museum of Los Angeles. The original came from an administrative manual of the Los Angeles County Superintendent of Schools, “Los Angeles County Government: Part I, Administration and Education,” dated March 1940.