The King who united England in 927 was King Athelstan the grandson of Alfred the Great.
Kingdom of England was created in 927.
year 927
In 1945, King George VI was king of the United Kingdom (which includes England).
No he was King of Great Britain and King of Ireland and then KIng of the United Kingdom but never of England.
King Alfred of Wessex is credited with the unification of England.
England became unified under the rule of King Æthelstan and his predecessors.
No. Depending on whether you count Egbert of Wessex (who was overlord of all the English kingdoms about AD 830) as a king of England, and on whether you consider England to have been united when Edward the Elder inherited the kingdom of Mercia (about 920) or not until Athelstan conquered Nothumbria (927), the first king of England was either Egbert or his great-grandson Edward the Elder, or Edward's son Athelstan. They were all Saxons, not Romans. If you are being very picky, then the Edward the Elder's title was not "King of England" but "King of the Angles and Saxons", and Athelstan's was "King of the English". The title "King of England" as opposed to "King of the English" was first used by Henry II, in 1154. Henry was a Frenchman (from Angers), not a Roman either.
George V was king of the United Kingdom (which includes England).
Alfred
No, he will be King (when it happens) of the United Kingdom
King George III was king of the United Kingdom (which includes England).
England, as a united country.