According to this history of formula, people made their own formula...

May 22, 2022 at 2:25 PM  ·  Comment — Archer T. Ships replied to Monica Anderson's comment.  ·  View on Facebook  ·  Markdown source

According to this history of formula, people made their own formula up through 1950's. Commercial formulas took over beginning in the 1960's. Most use cow's milk as a base. https://www.facebook.com/archerships/posts/10160479306990312