Norman invasion of Wales in the context of Puffin Island, Anglesey

The Anglo-Normans (Norman: Anglo-Normaunds, Old English: Engel-Norðmandisca) were the medieval ruling class in the Kingdom of England following the Norman Conquest. They were primarily a combination of Normans, Bretons, Flemings, Frenchmen, Anglo-Saxons and Celtic Britons.

After the conquest the victorious Normans formed a ruling class in England, distinct from (although intermarrying with) the native Anglo-Saxon and Celtic populations. Over time, their language evolved from the continental Old Norman to the distinct Anglo-Norman language. Anglo-Normans quickly established control over all of England, as well as parts of Wales (the Welsh-Normans). After 1130, parts of southern and eastern Scotland came under Anglo-Norman rule (the Scots-Normans), in return for their support of David I's conquest. The Anglo-Norman invasion of Ireland from 1169 saw Anglo-Normans and Cambro-Normans conquer swaths of Ireland, becoming the Irish-Normans.

Cambro-Normans (Latin: Cambria; "Wales", Welsh: Normaniaid Cymreig; Norman: Nouormands Galles) were Normans who settled in southern Wales and the Welsh Marches after the Norman invasion of Wales. Cambro-Norman knights were also the leading force in the Cambro-Norman invasion of Ireland, led by Richard de Clare, 2nd Earl of Pembroke in 1170.

The Kingdom of Dyfed (Welsh pronunciation: ['dəvɛd]), one of several Welsh petty kingdoms that emerged in 5th-century sub-Roman Britain in southwest Wales, was based on the former territory of the Demetae (modern Welsh Dyfed). The royal line was founded by Irish settlers in the 5th century. After the Norman invasion of Wales Dyfed was incorporated into Pembrokeshire. The name was resurrected for the now-defunct administrative area called Dyfed as well as in the names of some regional organisations such as Dyfed–Powys Police.

Dyfed may have originally occupied the area that bordered the rivers Teifi, Gwili and Tywi, and included contemporary Pembrokeshire, the western part of contemporary Carmarthenshire, and with the town of Carmarthen. Dyfed eventually comprised at least seven cantrefi: Cemais, Deugleddyf, Emlyn, Cantref Gwarthaf, Pebidiog, Penfro and Rhos, with an approximate area of about 2,284 square kilometres (882 sq mi).

Wales in the High Middle Ages covers the 11th to 13th centuries in Welsh history. Beginning shortly before the Norman invasion of the 1060s and ending with the Conquest of Wales by Edward I between 1278 and 1283, it was a period of significant political, cultural and social change for the country.

Magnus III Olafsson (Old Norse: Magnús Óláfsson, Norwegian: Magnus Olavsson; 1073 – 24 August 1103), better known as Magnus Barefoot (Old Norse: Magnús berfœttr, Norwegian: Magnus Berrføtt), was the King of Norway from 1093 until his death in 1103. His reign was marked by aggressive military campaigns and conquest, particularly in the Norse-dominated parts of Ireland and Britain, where he extended his rule to the Kingdom of the Isles and Dublin.

As the only son of King Olaf Kyrre, Magnus was proclaimed king in southeastern Norway shortly after his father's death in 1093. In the north his claim was contested by his cousin, Haakon Magnusson (son of King Magnus Haraldsson), and the two co-ruled uneasily until Haakon's death in 1095. Disgruntled members of the nobility refused to recognise Magnus after his cousin's death, but the insurrection was short-lived. After securing his position domestically, Magnus campaigned around the Irish Sea from 1098 to 1099. He raided through Orkney, the Hebrides and Mann (the Northern and Southern Isles), and ensured Norwegian control by a treaty with the Scottish king. Based on Mann during his time in the west, Magnus had a number of forts and houses built on the island and probably also obtained suzerainty of Galloway. He sailed to Wales later in his expedition, gaining the support of Anglesey (and the Gwynedd) after aiding against the invading Norman forces from the island.

Pembroke Castle (Welsh: Castell Penfro) is a medieval castle in the centre of Pembroke, Pembrokeshire in Wales. The castle was the original family seat of the Earldom of Pembroke. A Grade I listed building since 1951, it underwent major restoration during the early 20th century.

In 1093, Arnulf of Montgomery built the first castle at the site when he fortified the promontory beside the Pembroke River during the Norman invasion of Wales. A century later, the castle was given by Richard I to William Marshal, who became one of the most powerful men in 12th-century Britain. He rebuilt Pembroke Castle in stone, creating most of the structure that remains today. The castle is open to the public and is the largest privately owned castle in Wales.

The Kingdom of Gwynedd was a Welsh kingdom which first appeared at the turn of the sixth century. Based in northwest Wales, the rulers of Gwynedd repeatedly rose to dominance and were acclaimed as "King of the Britons" before losing their power in civil wars or invasions. The kingdom of Gruffudd ap Llywelyn—the King of Wales from 1055 to 1063—was shattered by a Saxon invasion in 1063 just prior to the Norman invasion of Wales, but the House of Aberffraw restored by Gruffudd ap Cynan slowly recovered and Llywelyn the Great of Gwynedd was able to proclaim the Principality of Wales at the Aberdyfi gathering of Welsh princes in 1216. In 1277, the Treaty of Aberconwy between Edward I of England and Llywelyn's grandson Llywelyn ap Gruffudd granted peace between the two but would also guarantee that Welsh self-rule would end upon Llywelyn's death, and so it represented the completion of the first stage of the conquest of Wales by Edward I.

Welsh tradition credited the founding of Gwynedd to the Brittonic polity of Gododdin (Old Welsh Guotodin, earlier Brittonic form Votadini) from Lothian invading the lands of the Brittonic polities of the Deceangli, Ordovices, and Gangani in the 5th century. The sons of their leader, Cunedda, were said to have possessed the land between the rivers Dee and Teifi. The true borders of the realm varied over time, but Gwynedd proper was generally thought to comprise the cantrefs of Aberffraw, Cemais, and Cantref Rhosyr on Anglesey and Arllechwedd, Arfon, Dunoding, Dyffryn Clwyd, Llŷn, Rhos, Rhufoniog, and Tegeingl at the mountainous mainland region of Snowdonia opposite.

Abergavenny (/ˌæbərɡəˈvɛni/; Welsh: Y Fenni, pronounced [ə ˈvɛnɪ], archaically Abergafenni, 'mouth of the River Gavenny') is a market town and community in Monmouthshire, Wales. Abergavenny is promoted as a "Gateway to Wales"; it is approximately 6 miles (10 km) from the border with England and is located where the A40 trunk road and the recently upgraded A465 Heads of the Valleys road meet.

Originally the site of a Roman fort, Gobannium, it became a medieval walled town within the Welsh Marches. The town contains the remains of a medieval stone castle built soon after the Norman conquest of Wales.