The Battle of Maes Cogwy (Maserfield) was fought on 5 August 641 or 642.

The seventh century in Britain seems to be a period where kingdoms continually strived to establish themselves.  There were many boundary shifts as they attempted to acquire new lands and defend existing ones  

In the build up to The Battle of Maes Cogwy, Cadwallon ap Cadfan, King of Gwynedd had driven Edwin of Northumbria from his kingdom and allied with Penda of Mercia in a counter attack, resulting in the Battle of Hatfield Chase in 633, at which Edwin was killed and the kingdom of Northumbria  temporarily collapsed.  The following year Oswald (Edwin's nephew), regained control of Northumbria, defeating and killing Cadwallon ap Cadfan at The Battle of Heavenfield.  It would appear that Oswald then went on the offensive against Penda and the Welsh kingdom of Powys as the next action occurs at The Battle of Maes Cogwy, which occurred at Oswestry ("Oswald's Tree"), now in Shropshire, but at the time in the kingdom of Pengwern (a sub-kingdom of Powys) 

The Battle of Maes Cogwy was fought on 5 August 641 or 642, between Oswald of Northumbria and an alliance between Penda, Cynyddylan ap Cyndrwyn of Powys and Cadwaladr ap Cadwallon of Gwynedd.  The outcome of the battle was defeat for the Northumbrians and the death of Oswald, which resulted in once again, the internal weakening and fracturing of the Northumbrian kingdom.  It strengthened the positions of Powys and Gwynedd and  left Penda as "the most formidable king in England."  

On 5th August 1063, Gruffydd ap Llywelyn was slain ‘through the treachery of his own men.’ (Map shows the extent of Gruffydd ap Llywelyn's Conquests) 

Gruffydd was undoubtedly the outstanding Welsh ruler of the 11th century and is remembered as  "the only Welsh king ever to rule over the entire territory of Wales".  He was known as the shield of Wales and the terror of its enemies.   He was a ruthless leader, with his hands stained with the blood of rivals and opponents alike, as he strove to drive Wales into a unified country and to defend it from its enemies. 

Gruffydd was born c. 1007, the son of Llywelyn ap Seisyll, King of Gwynedd and Deheubarth. On the death of his father in 1023, Gruffydd was forced into exile in Powys with his mother and sisters as Iago ab Idwal seized the throne of Gwynedd.  By 1055 he had become the ruler of Powys, recaptured Gwynedd and seized Deheubarth, Morganwg and Gwent.  This combined with his alliance with Aelgar of Mercia and their destruction of Hereford, put Gruffydd in a powerful position and in exchange for his fealty, King Edward the Confesser of England recognised Gruffydd's claim to sovereignty over the whole of Wales.  

  On the 5th of August 1925, Plaid Cymru ( The Party of Wales) was established.  

Its aims are to secure independence for Wales in Europe. To ensure economic prosperity, social justice and the health of the natural environment, based on decentralist socialism. To build a national community based on equal citizenship, respect for different traditions and cultures and the equal worth of all individuals, whatever their race, nationality, gender, colour, creed, sexuality, age, ability or social background. To create a bilingual society by promoting the revival of the Welsh language. To promote Wales's contribution to the global community and to attain membership of the United Nations.   

The founder members were Lewis Valentine and the academic and dramatist, Saunders Lewis. It was Saunders Lewis who was the party's first leader.   

Four years after the party's establishment, they fought their first general election in Caernarfon, North Wales in 1929. Though the candidate was unsuccessful, this campaign set the foundations for the party's intent. After the second world war, during the general election of 1950, they fielded seven candidates. In  1964,  the party fielded twenty-four candidates. During the  1960s,  the party went from strength to strength and in the 1966 by-election, Gwynfor Evans captured the seat of Caerfyrddin (Carmarthen), becoming the party's first MP in Westminster. Gwynfor Evans was the party's leader between 1945 and 1981.  

By  1970,  Plaid Cymru would fight every Welsh seat in parliamentary elections. This set the foundation for today, where Plaid Cymru fields a candidate for each Welsh seat in European, Westminster and Welsh Assembly elections as well as local council elections.  In 1981 Dafydd Wigley (MP for Caernarfon) became the party's leader. At the  time  Gwynfor Evans stepped down as party leader, but became far more well known in the struggle to secure a Welsh-language TV channel for Wales (the channel that was to become S4C).  

In the first election for the newly-established Welsh Assembly in 1999 Plaid Cymru became the second largest party, forming the official opposition to the Labour Party. This was a major breakthrough for Plaid Cymru, as they broke out of their traditional Welsh-speaking heartlands to capture seats in what was previously Labour's industrial heartland of South Wales.   

In 2007, following the Assembly Elections, Plaid Cymru became the second largest party in Wales with 15 seats and formed a government with the Labour Party.  The first time it had become a government party in its history.   

Born this day 1957 in Newport 

Eddie Butler - former Wales rugby international and captain, journalist and commentator.  He came to prominence as captain of the powerful Pontypool side  between 1982 and 1985.  Butler has also presented two TV history series "Wales and the History of the World" and "Hidden Histories"     

Born this day 1837, the son of an engineer from Merthyr 

William Thomas Lewis, 1st Baron Merthyr -  coal mining magnate. 

He first worked for the  Bute  Estate coal mining pits in Glamorganshire, before acquiring his own pits in The Rhondda, during the boom years for Welsh coal, which became known as Lewis Merthyr Consolidated Collieries Limited. He was also the founder of the Monmouthshire and South Wales Coal Association as a response the growing strength of the trade unions.  There is a statue of him in Aberdare Park. 

On 5th August 1645, King Charles I visited Colonel Edward Prichard at Llancaiach Fawr, a Tudor manor house near the village of Nelson as part of rallying tour through South Wales prior to the decisive Battle of Naseby during the English Civil War.  

When Civil War had broken out between King and Parliament in 1642 Colonel Edward Prichard was put in charge of the Royalist cause in Glamorganshire. However by the middle of 1645 support was waning and on 5th August King Charles I came on a rallying tour through South Wales and visited Llancaiach Fawr. Shortly afterwards the Prichards and many other Glamorgan gentry changed sides to support Parliament and Colonel Prichard subsequently defended Cardiff Castle against the Royalists.  

Llancaiach Fawr is considered to be one of the most important Gentry houses to have survived from the 16th and 17th century period.
Built for Dafydd ap Richard in 1530, the Manor, the original defensive design incorporated four-foot thick walls and stout wooden doors, which when securely closed, split the Manor in two and ensured that the inner east wing provided a safe and secure place of refuge during the troubled times.