Tiarnas Dyfed
Ar cheann de mhion-ríochtaí na Breataine Bige, a tháinig chun cinn sa chuid haois le meath impireacht na Róimhe, ab ea Ríocht nó Tiarnas Dyfed (Breatnais Teyrnas Dyfed).  Suite in iardheisceart na tíre, bunaithe ar iar chríocha na nDemetae (Breatnais Dyfed).  Tar éis ionradh na Normannach (1067 - 1100), tógadh Dyfed in Sir Benfro (Pembrokeshire sa Bhéarla) isteach faoin mbliain 1138.  Tógadh caisleán Normannach i bPenfro, faoi cheannas Marcher, Iarla Pembroke.

Eagrúcháin talún
 Cemref Cantref
 Sinsearach Neer
 An bhfuil Nyfer
 Pebidiog Cantref
 Rhos Cantref
 Cantref Daugleddau
 Pembroke Cantref
 Cantref Gwarthaf
 Efelffre
 Peuliniog
 Laugharne
 Amgoed (Henllan Amgoed)
 Stáiseanóireacht
 Leithinis
 Darach
 Elfed
 Emlyn
 Emlyn Is Cuch
 Cuach Sinsearach Emlyn

Ríthe Dyfed 

 Anwn ap Macsen (-394? )
 Ednyfed ap Anwn
 Clotri ap Ednyfed? (-421? )
 Iníon Clotri bean chéile Triffyn Bearded Irish
 Aircol Lawhir ap Triffyn (-515/527? )
 Gwrthefyr ap Aircol (-538/546? )
 Cyngar ap Gwrthefyr (-570? )
 Pedr ap Cyngar (-590? )
 Arthur ap Peter (598-615)
 Nowy Hen ap Arthwyr (615-650)
 Gwlyddien ap Nowy Hen (650-670)
 Caten ap Gwlyddien (670-690)
 Cadwgan Tredylig ap Caten (690-710)
 Rhain ap Cadwgan (710-730)
 Tewdos ap Rhain (730-760)
 Maredydd ap Tewdos (760-797)
 Rhain ap Maredydd (797-808)
 Triffyn ap Rhein (808-814)
 Owain ap Maredydd (809-811)

 Iddon / Tewdr ap Triffyn (-872/876? )
 Wonder iontach ap Bledrig (872-893)
 Llywarch ap Hyfigol (893-904)
 Rhodri ap Hyfigol (904-905)

Tagairtí