After avoiding Viscount Lovell's fleet sent by the king to stop him, Henry Tudor landed at Milford Haven on 7 August with a small force — consisting mainly of French and Breton mercenaries — in an attempt to claim the throne of England. Richard III had fought similar battles with Lancastrian usurpers in the past, and though Henry did not have his opponent's military experience, he was accompanied by his uncle, Jasper Tudor, 1st Earl of Pembroke (later 1st Duke of Bedford) and John de Vere, 13th Earl of Oxford, each a seasoned soldier. Henry gathered supporters in the course of his journey through his father's native Wales, and by the time he arrived in the Midlands, he had amassed an army of an estimated 5,000 men. The King, by contrast, could command nearly 8,000. The decisive factor in the battle was to be the conduct of the Stanley brothers — Sir William Stanley and Thomas Stanley, 2nd Baron Stanley, the latter being Henry's stepfather. Richard had good cause to distrust them, but was dependent on their continued loyalty.
Henry Percy, 4th Earl of Northumberland, with Lord Stanley and Sir William Stanley and their troops, watched the beginning of the engagement as the rest of Richard's army fought Henry's French mercenaries and loyal exiles. The Stanleys seem to have taken up a position some distance away from the two main armies. This was because Richard had taken Thomas Stanley's son and would kill him if he helped Henry. So the Stanley brothers waited until Henry was in a position where he would definitely win with their help. However if Henry was being destroyed by Richard they could help him and get Thomas' son back.
Richard reached Ambion Hill first where he organized his troops into three divisions on the hill. His troops were well-rested going into the battle, while Henry's men had trouble lining up on the rough ground below; it is unclear why. Richard might then have charged, slaughtering the disorganized Lancastrians, but he missed his chance. When Henry finally was ready, his men used cannon and arrows to force Richard to come down from his hilltop. When Richard did, he called for the Earl of Northumberland, who commanded the right wing of his army, to join in with fresh forces. But Percy refused, holding his forces back from action. There is some evidence that the difficult, wooded ground and narrow frontage of the Yorkist position prevented Northumberland from bringing his force up quickly, but it is far more likely that the Earl's dilatoriness was a calculated move. Although he was captured on the day, he was soon released and confirmed in all his titles and lands by the new King Henry VII, only to be murdered in a minor riot four years later. But it was the decision of the Stanleys, waiting nearby, that tipped the battle's outcome in favour of Henry.
Richard's commander, John Howard, 1st Duke of Norfolk, was slain, and the waiting armies of Lords Stanley and Northumberland still did not commit to any side. Richard was probably certain of treachery and his close staff counselled withdrawal. It was at this moment that Henry Tudor, also uncertain of the outcome, left the main body of his army and moved towards Lord Stanley, possibly to appeal to him in person. Upon seeing this, Richard attempted a charge against Henry's group. In the attack, Richard and his household hacked down Henry's small bodyguard of knights and even killed Henry's standard bearer, William Brandon, but at the moment Richard was within sight of Henry, Sir William Stanley's army chose to come to Tudor's rescue. They threw themselves into the fray surrounding Richard and the men of his Household, overwhelming them. In the fighting, Richard's own standard bearer, Sir Percival Thirwall, had both of his legs hewn away, possibly by a poleaxe or a hand-and-a-half sword. He did not let the banner fall, but instead held onto it until he was killed by one of the many retainers under Sir William Stanley joining the battle.
Richard himself was rumoured to have been killed by the poleaxe of a Welshman, and even sources of a hostile slant (notably Polydore Virgil) agree that he died fighting bravely. Richard III (Duke of Gloucester) was the last king of England to die in battle. Richard III was the only English king with a strongly northern association and powerbase, and the last of the Plantagenet kings. His body was taken ignominiously by the victors to Leicester, where it was paraded, battered and naked, through the streets, and was accidentally crushed against the parapet of a bridge over the River Soar. Richard's remains were eventually buried in the church which later became the city's cathedral, although legend has it that they were exhumed and thrown in the Soar. His probable resting place is thought to be under a Tesco's car park near the former site of the church of Greyfriars.
Henry Tudor was in fact outlawed and barred from his own inheritance, and was under Attainder when he seized the English Throne in 1485. His coronation conveniently nullified the attainder. Following this, Parliament made the declaration that any who had opposed King Henry at Bosworth were to be considered traitors.
The actual site of the battle has been the topic of often contentious debate among professional and amateur historians. For several years after the event the battle was called the Battle of Redemore and it was some time before the more famous name was used. This has led to the theory that the battle was not fought on Ambion Hill but on a reedy moor in the same area. An assault against a hill, as detailed in the official signage at the battlefield, can be discounted. Battles during the latter half of the Wars of the Roses had become more mobile in nature with commanders proving able to manoeuvre their hosts. People have long been researching to try to discover the actual site of this battle, work which has continued in the first decade of the 21st century. The lack of details and sometimes contradictory information in contemporary and near-contemporary sources makes both the chronology and location of the fighting extremely difficult to identify.
A compelling case is made for situating the battle closer to the villages of Dadlington and Stoke Golding, although most are agreed that Richard's encampment the night before the battle was indeed on Ambion Hill. If the hill played a role in the battle it is likely it was as an elevated platform for Richard's artillery. A visit to the modern site would suggest the surrounding countryside would be wide enough to support a medieval battle although the geography of the site in the fifteenth century remains harder to interpret. Another school of thought is that the battle actually took place at Merevale, just above Atherstone in Warwickshire; certainly reparations were made by the king to Atherstone after the battle. However, it is possible that the damages done were caused by troop movements or bivouacking by Tudor's men. Certainly the establishment of a chantry at Dadlington by the early sixteenth century for fallen men from the battle suggests the bulk of the fighting would have taken place in the vicinity. The suggestion (made by Michael K. Jones, the leading proponent of the Merevale relocation) that the dead were carted along the Roman road from the Merevale area to be buried at Dadlington is, perhaps, the weakest point of this thesis. What little is known of medieval battlefield burial practices (Towton, Visby) suggests that grave pits were dug in situ and that the bodies were packed together quite densely. Richer men were more likely to be taken away for interment in family tombs or to nearby religious establishments. Given the condition of the battlefield dead, the proximity to consecrated ground at Merevale (if the fighting took place nearby) and that it was late August makes the transportation of the bulk of the fallen in carts seem most unlikely.
The battle is also the setting for the very first episode of Blackadder, in which Richard III is victorious in the battle but is mistakenly decapitated by his great-nephew Prince Edmund (played by Rowan Atkinson) in defence of his horse, which the king attempts to borrow whilst Blackadder is urinating in nearby bushes. Looking at the decapitated head, Blackadder says, in realisation, "Oh my God, it's Uncle Richard!"
Science fiction author Andre Norton examined the counterfactual question, 'What if Richard had won the Battle of Bosworth?'. In her Crossroads of Time (1962), Richard is able to get to Henry and kill him in combat, therefore winning the field. Once secure on his throne, he further develops skills of government that are the subject of perennial debate between Ricardian and Tudor dynasty advocates in late 15th century English history.