https://en.wikipedia.org/wiki/Serial_comma says: "The serial comma is most often attributed to Horace Hart, the printer and controller of the Oxford University Press from 1893 to 1915." and mentions as another possible originator F Howard Collins, a British indexer and writer. Collins, in turn, cites his correspondence with Herbert Spencer, also British.
https://en.wikipedia.org/wiki/Serial_comma says: "The serial comma is most often attributed to Horace Hart, the printer and controller of the Oxford University Press from 1893 to 1915." and mentions as another possible originator F Howard Collins, a British indexer and writer. Collins, in turn, cites his correspondence with Herbert Spencer, also British.