Often, the surnames we have nowadays can differ from their ancestors of half a millennium ago. In the case of the three below the difference is subtle but nevertheless significant in identifying their origin.
There is a place called Trengrove in Menheniot, near Liskeard. But this was not the origin of the surname Trengrove. The Menheniot Trengrove was also spelt Trengof in the medieval period and is in fact an example of the common placename meaning smith’s farmstead. Like the placename the family name is a re-spelling of this more common name. The first example I’ve found is from the late 1590s in west Cornwall between Hayle and Camborne. Trengroves remained confined to this district until the 1800s when they headed eastwards (or maybe some Trengoves to the east independently began to add the <r> to their name.)
The surname Trenwith stems from a place in St Ives spelt Treyunwith in 1391 and Treunwith in 1508, meaning farmstead of the ash trees or possibly the farm of someone called Yunwith or similar. Sure enough, in 1524 we find a Thomas Treunwith at St Ives, one of the wealthiest men in that town. During the 1500s and 1600s the surname usually changed to Trenwith and some migration occurred to the east. This reached as far as Redruth (with a single example in east Cornwall at Calstock) by the 1700s. But it then contracted smartly back to West Penwith to huddle around Mount’s Bay in 1861, on the opposite side of the peninsula from its starting point.
Trescowthick only gained its <th> in the 1700s. Before then it was Trescowick or similar. It originated in the place also spelt Trescowick in the 1500s but now Trescowthick in Newlyn East south of Newquay. There a David Tresuyacke was living in 1543. The surname never strayed far from that part of mid-Cornwall until the eighteenth century, when branches sprouted both to the east and to the west.
Cornish studies resources 
Interesting about the ‘th’ coming and going. I live in ‘Treburrick’, St Eval, formerly known as ‘Treburthick’ (e.g. on the Martyn map c. 1780-1820) which has been attributed to one ‘Burthick’. I’m no linguist; is this a mutation which happened frequently?
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It was spelt Trebruthek in the 1320s. Although many Trev- names had a personal name as the second element, in this case it’s more likely to be from Cornish brythek, meaning dappled, possibly a stream name. The change in pronunciation from bruthek via burthek to burrek would be expected.
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Hello,
Any thoughts on the origins of the surname ‘Rule’ in Cornwall? The families have been there a long time, some argue it just appeared as was. The earliest Rule that can be found in Cornwall is Robert Rule buried in Camborne in 1619 and no evidence can currently be found of any ‘Rule’ before him. Some say that the name changed to Rule from Rollo. But i was wondering if you have other ideas on the evolution and changes in language.
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It’s in my book The Surnames of Cornwall. The name was originally spelt Rewell, Rele or Reyll and was around by the 1500s. It had multiple origins and I suggest it was most likely to be from an unidentified first name
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I find it quite interesting the way spelling just suddenly changes . I’ve always wondered how my surname, Vercoe, came from Varcoe and when that originated. I’ve been able to track my Vercoe heritage back to 1600s but haven’t yet gotten any further. I understand from a previous post you’ve seen it as far back as 1520s. Is there any way of looking back to when that separation may have originated?
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Hi Tom, The first example of Vercoe I have is an Elizabeth Verco, married at Crantock in 1583. Mind you, the first example of Varcow in the registers is only a year earlier, a baptism at St Ewe. I’m not sure there was a ‘seperation’ as such. Both spellings appeared fairly randomly and could switch from Var to Ver or vice versa into the 1800s. For example Maria Vercoe is baptised at St Ewe in 1610 and Willaim Varcoe baptised in the same parish in 1618. The father of both is named as Thomas – same man?
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What a fascinating subject. Will you be covering Greenaway/Greenwaie/ Greenaway/
Greenway? My family history research shows a connection with The Bude area since at least the sixteenth century. Thank you. Martyn Greenaway-Rowe
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