John (from Old French Johan, which itself had an origin in Hebrew Johanan) was a popular medieval first name, this popularity boosted by John the Apostle. It was so popular in fact that, in the 1400s, John had become the most common male first name in Cornwall. Yet, it wasn’t the most common surname in the early 1500s.
The pattern of its distribution as a surname at that point shows that it frequently occurred in mid and west Cornwall but had a patchier presence in the east, being absent from many parishes in north Cornwall. This could reflect the timing of hereditary surname adoption in Cornwall. In the English-speaking east surnames had been adopted by the late 1300s, much earlier than in west Cornwall where a sizeable proportion adopted a hereditary second name as late as the 1500s.
Johns, as it became, then tended to multiply more in the west although not to the same extent as Bennetts, our previous entry in the top 20.
Interestingly, John ended up switching almost entirely to Johns by 1861. By 1641 13 per cent were Johns, as opposed to John. A hundred years later Johns outnumbered John by two to one and by 1861 people named John made up just five per cent of the total. This was in stark contrast to Wales, where John remained the dominant form of the name.
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