Guernsey's modern constitution is rooted in Anglo-Norman history. The Channel Islands were integrated administratively into the Duchy of Normandy between the tenth and eleventh century and following the Battle of Hastings, the Duchy became closely associated with the English Crown. Soon after the French king conquered Normandy in 1204, the Islands returned to the dominion of the English king, who ruled them in his capacity as Duke of Normandy until, by the Treaty of Paris of 1259, Henry III formally abandoned this title. The treaty also confirmed the king's right to the Islands. In 1254, Henry had granted them, with much else, to his son, the future Edward I, stating that they may never be separated from the Crown and that no one may have any claim on them and that they should remain to the Kings of England forever. Thus the legitimate King of England came to be the legally recognised ruler of the Channel Islands although never incorporated in the United Kingdom. This is the origin of the Channel Islands' status as 'Crown Dependencies'.
Following the loss of Normandy, the king appointed a Warden or Keeper to represent his interests in the Channel Islands, overseeing defence, administering justice, collecting revenues, and organizing assizes. After 1473, the Bailiwicks and Guernsey and Jersey each had their own Wardens appointed and the office increasingly became known as Captain or Governor and in 1618 the Privy Council decreed that in Jersey the term governor should prevail. Around the same time this was adopted in Guernsey also.
As Governors were often resident in England, they usually appointed lieutenants who were resident in Guernsey to oversee affairs. By the nineteenth century the governorship itself had become a sinecure and the office was abolished in 1835. However, the practice of appointing Lieutenant-Governors continued, as it does today. A Lieutenant Governor is the personal representative of the Sovereign in the Bailiwick of Guernsey and is appointed by warrant of the Sovereign on the recommendation of the Lord Chancellor and Secretary of State for Justice in his capacity as Privy Councillor with special responsibility for the Channel Islands.
The office of the Lieutenant Governor is the official channel of communication between the Bailiwick's authorities and the United Kingdom. He submits citations recommending national honours and awards after consultation with the Bailiff of Guernsey, the President of Alderney and the Seigneur of Sark.
As the representative of Her Majesty, the Lieutenant Governor will hold investiture events, conferring medals or honours for long service and distinguished conduct.
The Lieutenant Governor also deals with certain immigration and national security issues and has responsibility for licensing shipping to Alderney and Sark.
The Lieutenant Governor also has power to appoint two members of the Board of Elizabeth College and the Priaulx Library.
Candidates for the office will invariably have distinguished themselves in military service.
The current Lieutenant Governor is Air Marshal Peter Walker who was sworn into office in April 2011.
The Bailiff of Guernsey is ex-officio the Deputy Lieutenant Governor with power to discharge the duties of Lieutenant Governor in his absence. In the absence of both the Lieutenant Governor and the Bailiff of Guernsey, the duty falls to be dealt with by the Deputy Bailiff of Guernsey and failing him the Senior Jurat of the Royal Court.