Henry Tudor, son of Edmund, Earl of Richmond, and the 13 year old Margaret Beaufort, was not born to be King of England. The baby boy that was born in Pembroke castle on the 28th January 1457 was born into a dangerous world, especially for a Lancastrian. In fact, Yorkists kidnapped him as a young boy when they took Pembroke castle, and he spent some time in the custody of the Duke Of York, who had claimed the throne just before Henry's birth.
In 1471, at the age of 14, he left Britain to live in exile in Brittany. While there, under the guardianship of his uncle Jasper, his preparation for kingship began. (He was one of the few remaining Lancastrian claimants in the 1470s.) Then in 1485, with the backing of the King of France, and still only 27, he began his bid for the English throne. He landed on the Welsh shore and marched through Wales to the midlands, gathering support as he went. He met Richard III and his forces just outside the small market town of Market Bosworth, where, for the last time in English history, an English king (Richard III) was defeated and killed in battle. Henry claimed the crown for himself (once it had been retrieved from a nearby bush - allegedly).
Historians don't really disagree about the events that took place before the Battle of Bosworth (22nd August 1485). The consternation arises over the ensuing events.
Historians disagree over whether Henry made drastic, moderate, little, even no, changes to the way in which the country was governed. One thing is for sure, and most historians are agreed on this, whatever he did it seemed to bring stability to the realm. England had been tormented by war and political faction in the 30 years prior to Bosworth, in a kind of long and drawn out civil war centred on the fates of two families - York and Lancaster. Henry's reign saw threats dealt with promptly and effectively, and long periods of peaceful relations with other countries. Henry's marriage to Elizabeth of York united the two warring families. The red rose of Lancashire was entwined with the white rose of Yorkshire to produce the Tudor rose. (Still on the rose theme, their first son, Arthur, was nicknamed 'The Rosebush of England'.)
The real historical issues concern Henry's dealings with the nobility, and his domestic policies. Whereas some historians stress change here others maintain that there was nothing new in Henry's policies. He was harsh with the aristocracy, and yet unwisely lenient with some who rebelled; he sought ways to increase the crown's coffers, and yet spent lavishly at court, leaving debts when he died; he sought a policy of peace but had a reputation as a warrior, leading his armies into battle himself; he tried to promote trade abroad but always made it obvious that commerce came second to dynastic priorities; he ruled by parliament, council and to some extent personally. What was this man? This King? Was he a planner, or did he react to events as they happened? How should we measure the level of his success?
Henry has had a reputation as a boring monarch. He wasn't touched by scandal once, in contrast with his son of the same name. He only married once! He didn't seek glory in warfare, he didn't try to overhaul the way the major institutions of the country were run, he lived beyond his teenage years, he didn't burn hundreds of his citizens, and he didn't have an Armada. His historical reputation has been dwarfed by the exploits of his son and grandchildren. He's the lesser known and yet perhaps the greatest of all the Tudor family.