 the welsh marches () is a term which, in modern usage, denotes an imprecisely defined area along and around the border between england and wales in the united kingdom. the precise meaning of the term has varied at different periods. the english terms welsh march, the march of wales, in medieval latin marchia walliae,often rendered in documents marcia wallie. were originally used in the middle ages to denote a more precisely defined territory, the marches between england and the principality of wales, in which marcher lords had specific rights, held to some extent independently of the king of england. ==origins: mercia and the welsh==  after the decline and fall of the roman empire which occupied britain until about ad 410, the area which is now wales comprised a number of separate romano-british kingdoms, including powys in the east. over the next few centuries, the angles, saxons and others gradually conquered and settled in eastern and southern britain. the kingdom of mercia, under penda, became established around lichfield, and initially established strong alliances with the welsh kings. however, his successors sought to expand mercia further westwards into what is now cheshire, shropshire and herefordshire. campaigns and raids from powys then led in the early 8th century to the building of wat's dyke, a boundary earthwork extending from the severn valley near oswestry to the dee estuary.john davies, a history of wales, penguin, 1993, isbn 0-14-028475-3trevor rowley, the welsh border - archaeology, history and landscape, tempus publishing, 1986, isbn 0-7524-1917-x as the power of mercia grew, a string of garrisoned market towns such as shrewsbury and hereford defined the borderlands as much as offa's dyke, a stronger and longer boundary earthwork erected by order of offa of mercia in the late 8th century. the dyke still exists, and can best be seen at knighton, close to the modern border between england and wales.david hill and margaret worthington, offa's dyke - history and guide, tempus publishing, 2003, isbn 0-7524-1958-7 in the centuries which followed, offa's dyke largely remained the frontier between the welsh and english. athelstan, often seen as the first king of a united england, summoned the british kings to a meeting at hereford in ad 926, and according to william of malmesbury laid down the boundary between wales and england, particularly the disputed southern stretch where he specified that the river wye 
16th_century_in_England EnglandaWales_border History_of_Wales Medieval_England