Situated on a high outcrop of rock above the river Tywi in south west Wales stands the castle of Dinefwr. Its position two miles downstream of the town of Llandelio meant that it guarded the western approach to the town from Carmarthen.

A 'castle', a wooden stockade, was first built on the site by the Welsh 'King' Rhodri Mawr,. However, by 960 A.D. the position had been strengthened and Hywel Dda ( ' Hywel the Good ' ) ruled much of Wales from Dinefwr, with the 'castle' becomming his principal court.

When the Normans began their incursions into Wales during the early part of the twelfth century, the powerful Gruffudd brothers held sway over the kingdom of Deheubarth. Because of the demise of his brothers by1163 the castle was in the possession of the youngest brother, Rhys ap Gruffudd the The Lord Rhys. His period of rule over Deheubarth was hard but fair and it offered a period of stability, however. conflict often occurred between himself and his sons during his later years

When the death of Lord Rhys occurred, Dinefwr became the scene of many conflicts between his sons.

During the latter part of the twelfth and early thirteenth centuries, the castle was again the scene of many conflicts, this time during the wars between the Welsh and the English. Indeed Rhys Gryg, the son of the Lord Rhys who fought for the English cause, was forced to dismantle the Castle by Llywelyn the Great, Prince of Gwynedd, who was pre-eminent in the area during the early part of the thirteenth century.

In the later part of the 13th century the English crown had to respond to the threat of the increasing power of Llywelyn ap Gruffudd 'Llywelyn the Last' of Gwynedd. When an English force met a Welsh one on a battlefield at Coed Llanthen near Llandelio, the ensuing battle resulted in a resounding English defeat. The castle at the time was in the hands of another son of Lord Rhys, Rhys Fychan, an alley of Llywelyn the Last.

When the death of Henry III occurred in 1272, Edward I came to the English throne. Within five years he had destroyed the power of the Welsh princes, In 1276 an English army under Pain de Chaworth was assembled at Carmarthen, and as it advanced up the Tywi valley Welsh resistance crumbled. Rhys Wedrod, at the time in control of Dinefwr placed the castle in the king's hands after which the castle remained largely in possession of the English crown.

After the castle was succeeded to the English crown, an English castellan was put in charge after which expenditure accounts inform us that repair work was undertaken in 1282-3. Surrounding ditches were cleaned out, the tower, bridge, hall and the "little tower' were repaired, a new gate was built and five buildings were erected within the outer ward. Further repairs were carried out in 1326. But as time past and tensions eased the English garrison moved out and the castle was left to fall into disrepair.