Last updated: 15 August 2008
The sheer length of Wales' border - 170 miles of open countryside - has been the critical factor in determining the nature of the sometimes difficult relationship between England and Wales, and migrations between the two countries.
The story starts after the Norman invasion of England in 1066, when King Henry I moved Flemish refugees from South East England to southern Pembrokeshire between 1107 and 1110.
To protect them, a line of over 50 castles and strongholds were built to protect Pembrokeshire from the indigenous Welsh, who were then moved to the hilly country in the north of the county. To this day, the area is described as 'Little England beyond Wales'.
By 1283, King Edward I of England had conquered the rest of Wales that had previously been under native control. Caernarfon Castle was one of the many castles built to consolidate Edward's hold on the principality. In some parts, such as the Vale of Clwyd, the Welsh were moved to the hills and the good farming land used to attract English settlers.
The industrial revolution
The industrialisation of South Wales in the 19th century brought an influx of workers from all over the world, and industralists and bosses, mainly from England. The bosses, so the story goes, quickly gathered a reputation for driving their employees ruthlessly and becoming fabulously wealthy in the process.
By the second half of the 19th century, pulled in by Wales' ever-growing demand for labour the English became the dominant immigrant group, and in particular people from the West country.
With their arrival in Wales came some of their traditions and culture, including a strong Wesleyan Methodist influence; and a passion for sports. Immigration tipped the linguistic balance between Welsh and English in many valley communities.
By the dawn of the 20th century, English migration into Wales had reached its peak. So much so, that in the large coastal towns at least, the line between Welshness and Englishness became more blurred than it had ever been.
The effect of war
The two world wars contributed to a sense of a shared fate that came to characterise the Welsh-English relationship - all summed up by the story of the evacuees during World War Two.
A staggering 200,000 children came from England to Wales in the early years of the war. Inevitably, with crowds of children from London's east end placed into the homes of Carmarthenshire farming families, there were many incidents of culture shock and antagonism.
Local people insisted on taking the evacuee children to chapel services, while there were concerns about a threat to Welsh culture. Roman Catholics were disturbed to find that the Welsh Protestant Sunday denied them not only their church, but their pub too!
But tensions were comparatively rare. Much more common were the stories of the lifelong attachments and friendships that grew out of the evacuee experience. Indeed, some enjoyed the experience so much, they decided to stay in Wales, become part of the community and speak the language.
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