4th gen Californian here, I lived in all three locations, Bay Area, LA and central valley. The author is right on a few things, and didn't address LA(blocked by paywall I guess). I'll go through them one by one.<p>San Francisco - One thing that the author missed is the post railroad growth. This was mainly due to a heavy military presence there(presidio, and a navy base at hunters point), my Grandfather who was in WWII was hanging out in SF alot waiting for deployments in the pacific theatre during the 1940's. The Navy and it being a shipping hub sustained the city until we can get into the 1960's which led to the hippie movement(Jack Kerouac and the beat movement before that) and people started flocking there and gave it its current liberal counterculture vibe. In addition the climate is very mild and I personally think its the best in the state(southern california is a bit too hot).<p>Los Angeles - I don't know what the author has to say about it, but you have the hollywood production houses starting in the 1920's, and also aerospace being a huge presence down there starting a bit before WWII, lockheed(skunkworks), Boeing and many more contractors flourished before and during the cold war, in addition Edwards airforce base was a huge draw for jobs as well and created alot of towns in the inland empire. Lastly the LA area is also a huge transportation hub as my Great Great grandfather(Santa Fe raiload vice president, moved to LA to run things in that area). Universities here include UCLA, USC and Clairemont colleges which led to a slew of talented people moving to the area. Why there are so many people in this area now is quite obvious, the weather is close to best in the world, but water is quite scarce and southern California has always had to supplement its water supply from the northern part of the state.<p>Central Valley - The 20th century was abnormally wet and rainy compared to California's natural climate which had hundred+ year droughts. But given the ample sunshine and enough rain it is basically one giant farm from Redding all the way to Bakersfield. The weather in the summer is really unbearable with triple digits being very common and humidity in the southern part of the valley. Read the grapes of wrath by John Steinbeck as it portrays the culture when it was starting out quite accurately - meaning huge farms exploiting farmworkers etc. There are not really any of the things in the 2 other areas, aerospace, military or world class universities so its population has been alot less, but that is changing as the coastal areas are becoming too expensive and the fastest growing areas are now in the central valley.