Excursus One - Anow

Dew cyfyt. Yd ys aid mi, Cyrt. Croas i yr eichur centav; taiht vyrr trei bywod yr Cymbry. Heddiw, disg du anu ig Cymbreg.

Du Anu ig Cymbreg - Your Name in Cymbric
Names in {brackets} are the literal translations of the English name.

Adda Adam
Aeron Aaron
Alech(ander) Alex(ander)
Alfred Alfred
Andre Andrew
Arthwr Arthur
Bena(myn) Ben(jamin)
Branyn Brandon
Cai Kai, Kay
Camyrn Cameron
Carl Charles, Carl, Karl, Carlos
Cenydd, Cainydd Kenneth
Colomen Callum
Eidyn Aidan, Aedan, Ethan
Daniel Daniel
David (pron. daavid), Dyfid David
Diag, Iac Jack
Dofnig Dominic
Dynfail Donald, Donall
Ewardd Edward
Eliod Elliot
Fred(ric) Fred(erick)
Giorg George
Grysdofr Christopher
Gwillem William
Hari Harry
Harvi Harvey
Henri Henry
Iagov, Iagow Jacob, James
Iohan John
Iosef Joseph
Iohyw Joshua
Isach Isaac
Iudas, Ywdas Judas
Lew Leo
Lewys , Lywes Lewis, Louis
Liym Liam
Luc Luke
Lugas Lucas
Mach Max
March Mark, Mark
Madai, Maidew Matthew
Michail, Mychel Michael
Morgan Morgan
Muhaved Muhammed, Mohammed
Nahan Nathan
Niglys Nicholas
Noha Noah
Olivr Oliver
Osgar Oscar
Owein, Ewein, Ewen Owen, Ewan
Padrig Patrick, Padhraig
Pawl Paul
Pedr Peter
Riant Brian
Riyn Ryan
Rovyrd Robert
Samwel Samuel
Stefan Steven, Stephen, Steffan
Stuyrt, {Iarl} Stuart, Stewart
Tobi Toby
Tomas Thomas
Sach Zach

NB: If your name's not on the list, let me know and I'll transliterate it for you.