Anne Boleyn (c.1501/1507 - 1536), the second wife of British King Henry VIII, was the first of his wives to be executed. She had been charged with treason, adultery and incest. She was originally ordered to be burned at the stake (the sentence for adultery), but Henry commuted her sentence to beheading.
Anne's primary crime was that of adultery (considered a form of treason), which she denied throughout her short imprisonment. At least four other men, accused of being her lovers, were also executed; only one man admitted to having had sex with Anne, but it is believed it was enticed through extreme torture. Anne was also accused of having incestuous relations with her brother, George, which he also denied. Historians believe the charges were created by Sir Thomas Cromwell, Henry's chief minister and aide, who had fallen into disfavor with Anne. Most historians believe that Anne was innocent of all charges and, for Henry, execution was a way to rid himself of her so he could continue his dalliances with his soon-to-be future queen, Jane Seymour.
King Henry wanted a male heir to his throne. Anne seemed incapable of giving him the heir he desired. He accused Anne of sorcery, adultery, and treason. He was already rid of wife number one, Catherine of Aragon, who died, and after beheading Anne, he would be free to pursue whomever he desired. Jane Seymour had already caught his interest, and he wanted Anne out of the way! Beheading seemed a logical solution.
Anne Boleyn, the second wife of Henry VIII, was sentenced to death for adultery, incest, and treason. The four men Anne was accused of sleeping with were also sentenced to death, and one of them was Anne's own brother, George Boleyn.
It was all planned and executed by Thomas Cromwell, who ploted Anne Boleyn's downfall and execution. Cromwell felt that Anne was a big threat to him as there had been many conflicts between the two. They have been arguing over the handling and distribution of monetary gains after the dissolvation of the monestaries and also about the foreign policy, forcing Cromwell to hatch up a plan to topple Anne from power as Queen in case she wreck his plans.
Also, Anne preferred a Franch Alliance while Cromwell desired a imperial alliance, showing the increase rift between the two. He did not want to lose this crucial alliance, so try to frame Anne so that she could not get what she want. If she was allowed to be continued on as Queen, the country would be plunged into deep waters, and he himself would be in dire straits, so he need to do something to bring down Anne.
He conspired with the Chapuys to bring down Anne and her family, so he arrested 5 men who were accused for sleeping with her, one of them that includes her own brother George Boleyn. Anne was charged with incest, treason and also adultery. However, there was only one of them who confessed that he had sleeped with her, but without enough concrete evidence, the jury denounced Anne's innocence and pronounced her guilty, and she was beheaded. Cromwell succeeded in overthrowing the Queen.
Other conspirary theories like her husband Henry had already known about the plot and also just after her death, Henry was chasing after another woman Jane Seymour, and also bethroned her, so leaving dobts whether Anne's execution was masterminded by Henry to wed Jane. Or the other theory where people thought that Anne was actually a witch, but all these groundless claims were unfounded.
The majority of historians now believe that Anne Boleyn was framed and was innocent of all charges. Unfortunately, Anne had argued with Cromwell over where the money was going from the Dissolution of the Monasteries and also over foreign policy. Cromwell was being pressured by Chapuys, the Imperial ambassador, to form an English/Imperial alliance but Anne was pro French and had a great influence over Henry VIII.
Cromwell realised that Anne's influence over Henry was too great and that it was putting the future of the country at risk and his own life at risk (Cromwell's predecessor, Thomas More, was executed). It got to the point that Cromwell knew it would be his life or her life.
Cromwell conspired with Chapuys and the Catholic Conservatives to bring Anne Boleyn down and replace her with meek and mild Jane Seymour, who would be no threat to anyone. Charging her with adultery hurt the king and meant that she and the men involved were guilty of treason - Cromwell could get rid of her and her supporters in one blow. Although Anne had alibis for many of the occasions when she was meant to be with other men, and although only one of the 5 men confessed (Smeaton, under torture), she was tried, found guilty and executed on the 19th May 1536.
Anne and Henry's marriage was actually annulled the day before she was executed, so there was actually no need to behead her for adultery. However, Cromwell had to get rid of her once and for all.
This is a rather simplistic explanation, but her execution was down to Cromwell. See the Eric Ives Biography on her life and also:-
Anne Boleyn always had deep aspirations for becoming the wife the King. She would let nothing stand in her way. As we all have learned, greed will eventually lead to one's downfall and Anne Boleyn was no exception. She was sentenced to death for committing adultery and for treason against her country. Unfortunately, one of the men she was accused of adultery with would be her own brother, who also met his demise. In the end, Anne Boleyn was beheaded for her devious actions.