Although Richard III was first published in 1597, most scholars believe that this play about the rise and fall of a wicked king was written several years earlier, probably in 1592 or 1593, and first performed shortly afterward. Evidence shows that it was popular from the beginning: The Elizabethan actor Richard Burbage achieved distinction playing Richard III, and the character's final line—"A horse! A horse! My kingdom for a horse!" —was already famous by the early 1600s when Richard Corbet (1618 or 1621) wrote a poem about the play. It is also believed that Elizabethan audiences would have appreciated the patriotic speech given by Richmond (who becomes King Henry VII) in the last act.

Early critical assessment of Richard III was mixed. Sir William Cornwallis (1600) and William Winstanley (1660), for example, objected to Shakespeare's portrayal of King Richard as "a monster." In contrast, poet John Milton (1650) argued that the character in the play was "true to his historical counterpart." Today, most scholars contend that Shakespeare based the drama and its characters primarily on Edward Hall's The Union of the Two Noble and Illustre Famelies of Lancastre and Yorke (1548)—a work that relies both on fact and fiction to tell the history of King

Richard III's family (the House of York) and its long power struggle (known as the Wars of the Roses) with King Henry VII's family (the House of Lancaster). A secondary source was probably Raphael Holinshed's Chronicles of England, Scotland, and Ireland (1587). In turn, each of these works was based upon Thomas More's witty and ironic Historie of King Richard the Thirde (published around 1513). In this account, More used a dry, almost humorous tone to describe Richard as hunchbacked, tyrannical, and evil.

Shakespeare's play varies from its sources in numerous ways but two are of particular importance: First, although Shakespeare borrowed Thomas More's ironic narrative tone, he placed it in Richard's mouth, so that the character becomes a complex, semi-comical villain who laughs at himself and others even while he is plotting to do harm.

Richard III also functions as a sequel to Shakespeare's trilogy of plays—Henry VI, parts one, two, and three which brings us to the second of Shakespeare's significant modifications: In Richard III, Margaret, widow to Henry VI (a Lancastrian king who was murdered by Richard in Henry VI, part three), remains in England where the play is set rather than sailing home to France as she did according to history. Onstage, Margaret voices her opinion on the action in the play, and predicts doom and misery as her revenge on Richard and his supporters. In doing so, Margaret serves the same function in the drama as a chorus would. Individual choric figures or a chorus are sometimes used to describe events which occur before the beginning of the play or to comment on the action of the playas it unfolds.

Richard's complexity and Margaret's presence have generated much critical discussion regarding the play's themes of sin and divine retribution. Richard's coronation comes toward the end of a period of bloody civil strife known as the Wars of the Roses, and some critics argue that his wickedness functions as divine punishment against the warring parties, as well as a method of cleansing England for a new era of peace. Other critics have focused on Margaret and her importance to the development of the play, as her curses on each guilty character are fulfilled.