Robert Cecil was the son of Elizabeth I's chief minister Lord Burghley, he was a courtier, a successful politician, and an administrator who took over his father's role in government when he became too ill to do the job himself. In 1596, Cecil became Elizabeth's secretary and out-maneuvered her favourite Robert Devereux resulting the what history calls Essex's Rebellion, thus eliminating any rivals to his position as the queen's minister. He was also responsible for the smooth transfer of the crown to James VI of Scotland on Elizabeth's death in 1603. On the succession of James to the English throne, he temporarily lost some of his influence as James had been a supporter of Essex, but the king came to trust and rely on Cecil, eventually calling him his 'little beagle'. In 1605 Cecil quashed yet another rebellion - the infamous Gunpower Plot, although it is thought that Cecil was actually behind the plot with the aim of convincing James that he should not trust those of the Catholic persuasion.
How sad is it then that both Elizabeth I and James I referred to Cecil in an unkind manner, Elizabeth is said to have called him her pygmy and a monkey, and James called him a beetle, and after all he had done for them too! It is highly likely that Shakespeare was referring to Robert Cecil, as the unpopular hunchback, when he was writing his play Richard III, and this is captured very well in the 2011 film Anonymous where he is portrayed as a small dark creature, underhand, and skulking.