The most authoritative and balanced biography of Edward II is J. R. S. Phillips, Edward II (New Haven, Conn., and London: Yale University Press, 2010). R. M. Haines, King Edward II: Edward of Caernarfon, His Life, His Reign, and Its Aftermath, 1284–1330 (Montreal and London: McGill-Queen’s University Press, 2003), is less comprehensive but strong in certain areas, notably the king’s relations with the episcopacy. The king’s boyhood and upbringing are examined in detail in H. Johnstone, Edward of Carnarvon, 1284–1307 (Manchester: Manchester University Press, 1946), and the standard biography of his father is M. Prestwich, Edward I (Berkeley, Calif.: University of California Press, 1988). The Reign of Edward II: New Perspectives, edited by G. Dodd and A. Musson (Woodbridge: York Medieval Press, 2006), is a thought-provoking collection of essays.
As well as the king, many of the chief figures of the reign have found their biographers. The almost simultaneous publication in the early 1970s of J. R. Maddicott, Thomas of Lancaster 1307–1322: A Study in the Reign of Edward II (Oxford: Oxford University Press, 1970), and J. R. S. Phillips, Aymer de Valence, Earl of Pembroke, 1307–1324: Baronial Politics in the Reign of Edward II (Oxford: Oxford University Press, 1972), swept away the ‘constitutional’ approach to the politics of the reign and brought the focus to bear on familial and territorial disputes. Gaveston’s career and relationship with Edward are examined, with significant differences of emphasis, in J. Hamilton, Piers Gaveston, Earl of Cornwall, 1307–1312: Politics and Patronage in the Reign of Edward II (Detroit and London: Wayne State University Press, 1988), and P. Chaplais, Piers Gaveston: Edward II’s Adoptive Brother (Oxford: Clarendon Press, 1994). There are pacy biographies of Queen Isabella and Roger Mortimer: P. Doherty, Isabella and the Strange Death of Edward II (London: Constable, 2003), and I. Mortimer, The Greatest Traitor: The Life of Sir Roger Mortimer, 1st Earl of March, Ruler of England 1327–1330 (London: Jonathan Cape, 2003), both of whom doubt that Edward was murdered in Berkeley Castle in 1327, although their conjectures as to his eventual fate are very different. The best accounts of the Younger Despenser’s activities are N. Fryde, The Tyranny and Fall of Edward II, 1321–1326 (Cambridge: Cambridge University Press, 1979), and M. Buck, Politics, Finance and the Church in the Reign of Edward II: Walter Stapeldon, Treasurer of England (Cambridge: Cambridge University Press, 1983), which provide detailed accounts of the last years of Edward’s reign. The king’s imprisonment at Berkeley Castle and his tomb in Gloucester Cathedral are thoroughly analysed in J. Barlow, R. Bryant, C. Heighway, C. Jeens and D. Smith, Edward II: His Last Months and His Monument (Bristol: Bristol & Gloucestershire Archaeological Society and Past Historic, 2015).
For Robert Bruce, it is still well worth reading G. W. S. Barrow, Robert Bruce and the Community of the Realm of Scotland (Edinburgh: Edinburgh University Press, 1965; third edition 1988), but see now also M. Penman, Robert the Bruce, King of the Scots (New Haven, Conn., and London: Yale University Press, 2014). Bannockburn is admirably contextualized by M. Brown, Bannockburn: The Scottish War and the British Isles, 1307–1323 (Edinburgh: Edinburgh University Press, 2008). The fullest account of the Scottish impact on northern England and Ireland is C. McNamee, The Wars of the Bruces: Scotland, England and Ireland 1306–1328 (East Linton: Tuckwell Press, 1997). For the geopolitics and ethnic complexity of Wales at this time, see R. R. Davies, Lordship and Society in the March of Wales, 1278–1400 (Oxford: Oxford University Press, 1978). For the European famine of 1315–17, see W. C. Jordan, The Great Famine: Northern Europe in the Early Fourteenth Century (Princeton, NJ: Princeton University Press, 1996), and for the impact of government policies on the peasantry, J. R. Maddicott, The English Peasantry and the Demands of the Crown, 1294–1341, Past and Present Supplement No. 1 (Oxford: Past and Present Society, 1975).
The two most interesting chronicles of the reign are (for court politics) Vita Edwardi Secundi: The Life of Edward the Second, edited and translated by W. R. Childs, Oxford Medieval Texts (Oxford: Clarendon Press, 2005), and (for northern affairs) The Chronicle of Lanercost, 1272–1346, edited and translated by Sir Herbert Maxwell (Glasgow: Glasgow University Press, 1913). Most of the key documents of the reign are collected in English Historical Documents, III: 1189–1327, edited by H. Rothwell (London: Eyre and Spottiswoode, 1975). There is also a collection of Edward II’s early letters: Letters of Edward Prince of Wales, 1304–1305, edited by H. Johnstone (Cambridge: Roxburghe Club, 1931).