The current welsh flag that we use and wear with pride was first used by Henry VII, the Welsh King of England and founder of the Tudor dynasty.
The flag incorporates the Red Dragon of Cadwaladr, King of Gwynedd, along with the Tudor colours of green and white. It was used by Henry VII at the Battle of Bosworth Field in 1485 after which it was carried in state to St Paul's Cathedral. The red dragon was then included in the Tudor royal arms to signify their Welsh descent. It was officially recognized as the Welsh national flag in 1959.
Flag of Gwynedd Gwynedd petty kingdom of several Welsh successor states which emerged in 5th-century post-Roman Britain in the Early Middle Ages, and later evolved into a principality during the High Middle Ages.
It was based on the former Brythonic tribal lands of the Ordovices, Gangani, and the Deceangli which were collectively known as Venedotia in late Romano-British documents. Between the 5th and 13th centuries Gwynedd grew to include Ynys Môn and all of north Wales between the River Dyfi in the south and River Dee (Welsh Dyfrdwy) in the northeast. The Irish sea (Môr Iwerddon) washes the coast of Gwynedd to the west and north and lands formerly part of the Kingdom of Powys border Gwynedd in the south-east.
Gwynedd's strength lay in part due to the region's mountainous geography which made it difficult for foreign invaders to campaign in the country and impose their will effectively. Popular tradition attributed to Nennius, a 10th-century Welsh chronicler, traced Gwynedd's foundation to Cunedda. According to Nennius, Cunedda migrated with his sons and followers from Brythonic Lothian, in southern Scotland, in the 5th century.
The main court of the Kingdom of Gwynedd was originally at Deganwy Castle, where Maelgwn Gwynedd (died 547) had his stronghold. The senior line of descendants of Rhodri the Great would make Aberffraw on Ynys Mon as their principal seat until 1170. In the thirteenth century, Llywelyn Fawr, his son Dafydd ap Llywelyn and grandson Llywelyn ap Gruffudd had Abergwyngregyn on the north coast as their home.
Flag of Llywelyn Ein Llyw Olaf
Llywelyn ap Gruffydd or Llywelyn Ein Llyw Olaf ('Llywelyn, Our Last Leader') (c. 1223 – 11 December 1282), sometimes rendered as Llywelyn II, was the last prince of an independent Wales before its conquest by Edward I of England.
Flag of Owain GlyndŵrOwain Glyndŵr or Owain Glyn Dŵr, anglicised by William Shakespeare as Owen Glendower (c. 1354 or 1359 – c. 1416), was a Welsh ruler and the last native Welshman to hold the title Prince of Wales. He instigated an ultimately unsuccessful but long-running revolt against English rule of Wales
Source: Wikipedia - Flag of Wales