Scottsdale spent 1919 at the top of the arc, hanging there. The war was over and wartime procurement was gone — yet cotton prices, running on momentum and speculation, kept climbing anyway. The fields around town stood in Pima cotton to the fencerows, the gins kept working, and the population was headed for 1,047 at the 1920 count, up from 267 a decade earlier.
Every farmer in the Valley knew the sensible move was to diversify before the wartime market’s ghost gave out. Almost nobody did — a monoculture paying those prices is very hard to argue with. So the town closed its decade richer than it had ever been, with new Mexican-American families putting down permanent roots south of the townsite and its entire livelihood staked on one commodity.
The price collapsed in 1920–21, from more than a dollar a pound toward a dime. What Scottsdale built out of the wreckage — a real Main Street, a bank, a newspaper, and its first paying winter guests — opens the 1920s chapter.