David Dudley Field II was a jurist who drafted a code of laws which was adopted by New York state. After this, motivated by his study of English common law, he made an updated code of laws which included a provision banning noncompete agreements.
This model code was not accepted by New York, and just floated around for a while, until it happened to be on hand when California was becoming a state, with nobody thinking much about noncompete agreements.
North Dakota also adopted the Field Code and also bans noncompetes.
https://www.restrictivecovenantreport.com/2013/01/north-dako...