List of rulers in Wales

This is a list of rulers in Wales (Welsh: Cymru; and neighbouring regions) during the Middle Ages, between the 5th and 16th centuries. The rulers were monarchs who ruled their respective realms, as well as those who briefly ruled the Principality of Wales. These former territories are now within the boundaries of modern-day Wales and the neighbouring Welsh Marches in England (both in the United Kingdom).

Before the Edwardian Conquest, completed in 1283, Wales consisted of several independent realms, the most important being Gwynedd, Powys, Deheubarth (which was formed from lands belonging to Ceredigion, Dyfed and latterly Seisyllwg) and Morgannwg (formed from Glywysing and Gwent). Boundary changes and the custom of dividing patrimonies between heirs meant that few princes ever came close to ruling the whole of Wales.

The names of those known to have ruled over one or more areas are listed below. Boundaries changed frequently. The only known native ruler of all of present-day Wales was Gruffudd ap Llywelyn (c. 1010–1063), a Prince of Gwynedd who became King of Wales from 1055 to 1063. However, some Welsh princes sporadically claimed the medieval title of "Prince of Wales" between the 13th to 15th centuries. The title remains in use but is given to heirs apparent of English and British monarchs.