source : http://www.royal.gov.uk/
Edward II had few of the qualities that made a successful medieval king. Edward surrounded himself with favourites (the best known being a Gascon, Piers Gaveston), and the barons, feeling excluded from power, rebelled. Throughout his reign, different baronial groups struggled to gain power and control the King.
The nobles' ordinances of 1311, which attempted to limit royal control of finance and appointments, were counteracted by Edward. Large debts (many inherited) and the Scots' victory at Bannockburn by Robert the Bruce in 1314 made Edward more unpopular.
Edward's victory in a civil war (1321-2) and such measures as the 1326 ordinance (a protectionist measure which set up compulsory markets or staples in 14 English, Welsh and Irish towns for the wool trade) did not lead to any compromise between the King and the nobles.
Finally, in 1326, Edward's wife, Isabella of France, led an invasion against her husband. In 1327 Edward was made to renounce the throne in favour of his son Edward (the first time that an anointed king of England had been dethroned since Ethelred in 1013). Edward II was later murdered at Berkeley Castle.