Kingdom of England originated as a unified realm in 927, over the year the realm shaped the local political landscape, the kingdom fought France for 116 years and almost won, they tried to annex Scotland several times and in 1171 an Englishmen ascended to the Papacy. He created the Laudabiliter Bull, which gave the Kings a claim on Ireland, the Norman Conquest led to the later Personal Union of England and Ireland. Following the Hundred Years War, Black Plague and the War of the Roses, the crown was now no longer considered to be god given and their power over Ireland was almost lost, though their possession of Wales was unaffected.
Before Henry VIII
As the War of the Roses dragged on, it appeared that the House of York would succeed, on 21 May 1471 Henry VI of England died and Edward IV seemed victorious, however a descendent of Edward III through the Beaufort family called Henry Tudor became the Lancaster claimant. After the usurpation of England by Richard III and the death of Edward IV's sons, Henry Tudor claimed the throne. Richard III died and Henry became king, however John of Gaunt made it clear that the Beauforts and their descendants won't be able to succeed. Thus Henry had to marry Edward IV's daughter Elizabeth. Henry VII was a great monarch, he was good with foreign realms, increased the economic power of England and served justice. His son Arthur was married to the Spanish princess Catherine, however Arthur died of an illness. Now a second-born Henry became the heir, to renew the alliance Catherine now married her former brother-in-law.
Henry VIII ascended to the throne early and young. Crowned on the 24th June 1509 and started in a diplomatic fashion similar to that of his father. His family life was however problematic, Catherine suffered miscarriages and some children died early. In 1514 he finally had a son called Henry and in 1516 a daughter Mary, she was later given in marriage to the future King of France, thus ending a great rivalry from the war over the french throne.
Henry VIII had himself crowned as the King of Ireland and expanded the rule. He took an interest in a alliance with Scotland established by his father. Upon the betrayal of James V of Scotland by Archibald Douglas, Henry VIII made sure his great-nephew Robert IV of Scotland would stay king and likely saved House Stewart from destruction.
Seeing there might be a dispute between Portugal and Spain, he allied with Portugal as well, under those circumstances he might refuse a call to arms, on the basis of being allied with both parties. He signed the Renewed Treaty of London with Charles V, Holy Roman Emperor and Francis I of France.
From his wound during the Scottish War he was slowly in need of regent and in 1543 he died from an infected wound, the ascension of the spoilt and cowardly Henry IX almost destroyed England and nearly sent it to the dustbin of history.
Henry IX was also a part of the Scottish War, however it scared him and he turned to a life of secret plotting. During Henry VIII's reign the young Heir to the Portuguese throne suddenly died, most people suspected the future husband to Princess Maria of Portugal. His intrigue later broke up the remainder of the feudal system. When he finally died it was secretly celebrated. When John III of Portugal was near dead, he said that Portugal would follow the French Salic Law. His two brothers had religious positions, so the second youngest Louis I came to the throne. Arthur I then declared war, however he was really bad in the art of war, so the superior English army was forced to attack the capital from the sea, however Louis made a blockade and the army took a major disaster. After the war between 1573 and 1576 Arthur was dethroned and exiled.
Believing the ascension of Arthur's daughter Elizabeth, Edward was suddenly pulled into politics. Soon the Irish group of rebel nobles called Frith-Béarla became a problem. Eventually they rebelled as the Kingdom of Éire. However, they were crushed and Edward VI ruled in peace and prosperity until 1602, he expanded a bit more west in America, actually claiming America as a kingdom. He also created colonies in Africa, mainly near the Ivory Coast.