From http://en.wikipedia.org/wiki/Wars_of_the_Roses - all links below refer to the source.

The Wars of the Roses were a series of dynastic wars fought between supporters of two rival branches of the royal House of Plantagenet: the houses of Lancaster and York (whose heraldic symbols were the "red" and the "white" rose, respectively) for the throne of England. They were fought in several sporadic episodes between 1455 and 1485, although there was related fighting both before and after this period. The final victory went to a relatively remote Lancastrian claimant, Henry Tudor, who defeated the last Yorkist king Richard III and married Edward IV's daughter Elizabeth of York to unite the two houses. The House of Tudor subsequently ruled England and Wales for 117 years.

Henry of Bolingbroke had established the House of Lancaster on the throne in 1399 when he deposed his cousin Richard II and was crowned as Henry IV. Bolingbroke's son Henry V maintained the family's hold on the crown, but when Henry V died, his heir was the infant Henry VI. The Lancastrian claim to the throne descended from John of Gaunt, 1st Duke of Lancaster, the fourth son of Edward III. Henry VI's right to the crown was challenged by Richard, Duke of York, who could claim descent from Edward's third and fifth sons, Lionel of Antwerp and Edmund of Langley, 1st Duke of York. Richard of York, who had held several important offices of state, quarrelled with prominent Lancastrians at court and with Henry VI's queen, Margaret of Anjou.

Although armed clashes had occurred previously between supporters of York and Lancaster, the first open fighting broke out in 1455 at the First Battle of St Albans. Several prominent Lancastrians died, but their heirs continued a deadly feud with Richard. Although peace was temporarily restored, the Lancastrians were inspired by Margaret of Anjou to contest York's influence. Fighting resumed more violently in 1459. York and his supporters were forced to flee the country, but one of his most prominent supporters, the Earl of Warwick, invaded England from Calais and captured Henry at the Battle of Northampton. York returned to the country and became Protector of England, but was dissuaded from claiming the throne. Margaret and the irreconcilable Lancastrian nobles gathered their forces in the north of England, and when York moved north to suppress them, he and his second son Edmund were killed at the Battle of Wakefield in December 1460. The Lancastrian army advanced south and recaptured Henry at the Second Battle of St Albans, but failed to occupy London, and subsequently retreated to the north. York's eldest son, Edward, Earl of March, was proclaimed King Edward IV. He gathered the Yorkist armies and won a crushing victory at the Battle of Towton in March 1461.

After Lancastrian revolts in the north were suppressed in 1464 and Henry was captured once again, Edward fell out with his chief supporter and advisor, the Earl of Warwick (known as the "Kingmaker"), and also alienated many friends and even family members by favouring the upstart family of his queen, Elizabeth Woodville, whom he had married in secret. Warwick tried first to supplant Edward with his younger brother George, Duke of Clarence, and then to restore Henry VI to the throne. This resulted in two years of rapid changes of fortune, before Edward IV once again won complete victories at Barnet (April 1471), where Warwick was killed, and Tewkesbury (May 1471) where the Lancastrian heir, Edward, Prince of Wales, was executed after the battle. Henry was murdered in the Tower of London several days later, ending the direct Lancastrian line of succession.

A period of comparative peace followed, but King Edward died unexpectedly in 1483. His surviving brother, Richard of Gloucester, first moved to prevent the unpopular Woodville family of Edward's widow from participating in the government during the minority of Edward's son, Edward V, and then seized the throne for himself, using the suspect legitimacy of Edward IV's marriage as pretext. Henry Tudor, a distant relative of the Lancastrian kings who had inherited their claim, defeated Richard at Bosworth in 1485. He was crowned Henry VII, and married Elizabeth of York, daughter of Edward IV, to unite and reconcile the two houses.

Yorkist revolts, directed by John de la Pole, 1st Earl of Lincoln and others, flared up in 1487 under the banner of the pretender Lambert Simnel, who claimed to be Edward, Earl of Warwick (son of George of Clarence), resulting in the last pitched battles. Although most of the surviving descendants of Richard of York were imprisoned, sporadic rebellions continued until 1497 when Perkin Warbeck, who claimed to be the younger brother of Edward V, one of the two disappeared Princes in the Tower, was imprisoned and later executed.

From: http://www.bosworthbattlefield.com/battle/thebattle.htm

Bosworth is a site of national historic significance, being the location of one of the three most important battles fought on British soil. It is the site where the Battle of Bosworth took place in 1485, and infamous as the place where King Richard III lost his life and crown to Henry Tudor and thus where the Tudor dynasty was born. Shakespeare immortalised Richard III, a King betrayed, unhorsed, surrounded by his enemies and finally calling out “A horse, a horse, my kingdom for a horse.”

The Wars of The Roses consisted of a series of battles fought between 1454 and 1485 by two rival branches of the same royal family for the control of the English throne. A contemporary name for the conflict was 'The Cousins' War'.Although some members of the houses of York and Lancaster did have white and red roses on their heraldry, the term Wars of the Roses was not used untill much later.

Between 1454 and 1471 the houses of Lancaster and York fought thirteen battles with the Yorkist Edward IV winning the eventual victory. Richard III was Edward’s youngest brother and succeeded him to the throne in 1483. Fourteen years after the last battle of the Wars of the Roses, Richard III rode into battle once more, losing his life and his throne to Henry Tudor on the 22^nd August 1485. On this date, in the heart of rural Leicestershire, two armies faced each other; a large Royal army led by King Richard III awaited the approach of a smaller rebel army led by Henry Tudor, Earl of Richmond. This decisive battle would witness the death of the King and the birth of a dynasty that would last for 122 years. It was the last time that an English King was killed in battle.

King Richard III had ruled the country for just over two years when he found his claim to the throne challenged by Henry Tudor. Henry started the day as an exiled nobleman, and ended the day being crowned at Stoke Golding, becoming Henry VII.  Henry had been living in exile in France since the age of 14, but at 28 was encouraged by his Lancastrian family and friends to fight for the chance to become England’s King. He sailed to Milford Haven in Wales with a small army of English exiles and French mercenaries. He was born in Wales, and used this connection to gain more support for his cause. His army finally numbered around 5000 men.

Henry requested help from Lord Thomas Stanley and his brother Sir William Stanley, based in the North West of England. Lord Thomas was married to Henry’s mother (Henry’s father had died some years before), but more importantly, was a wealthy man. He could command a great private army. Henry and Sir William are said to have communicated on the march down the country, as they would have followed a similar route. However it is not known if Henry was successful in gaining Lord Thomas’s support prior to the Battle. Meanwhile Richard III, on hearing of Henry’s landing, sent out a summons to his supporters, requesting them to meet the King equipped for war. He also wanted Lord Thomas’s support and took his eldest son hostage in an attempt to guarantee it.

Richard was buried at Grey Friars monastery in Leicester. Years later, when England’s monasteries were being destroyed by Henry VIII, Richard’s bones were dug up and thrown in the river  - he is one of the few English Kings not to have a grave. ((we now know this is not true as I stated above this was an 'invention of the 16th C) Henry VII, the new King of England married Richard III’s niece, Elizabeth, joining the Houses of York and Lancaster together. Despite this union Yorkist revolts continued until 1499. You can read the remainder of this epic saga on the link on top of this section.