Linda:
Henry VIII of course was not childless - though he considered having a daughter the same as having no child at all.
Sorry - I missed this.
Did you see the TV series "Pillars of the Earth"? It was one of those seven part historical costume pieces set in the first time (which was also the the last time before Henry VIII) a woman tried to inherit the throne of England. That period was called "the anarchy" and was basically a decades long civil war. One that only ended when the "a girl can't be king so I'm calling myself king" guy named the Queen's son as his heir.
Henry VIII knew all about civil war - the War of the Roses was ended by Henry VIII's dad (Henry VII) and there were still a few people out there who might have had a better claim to the throne than Henry VIII. Henry VII raised VIII with that in mind - hammering in how the country couldn't be split (and to always kill your relatives if they gave you the slightest excuse).
What happened when Henry VIII's son died? A battle for the throne between the rightful heir (Lady Jane) and and VIII's bastard daughter (when the marriage was annulled Mary was effectively declared a bastard). Okay, so it wasn't much of a war (nor was the rebellion that followed) but if Lady Jane had been able to rally more of England it would have become a serious fight. A protestant - catholic war like the ones that ravaged Germany.
And Bloody Mary's marriage to Philip II of Spain is one of the things that led to English - Spanish wars and was one of the things that kept Elizabeth "the virgin queen".
Goodgulf