Robert Stillington was a doctor of civil law who began his church career in the 1440s. He was one of Henry VI’s councillors by 1449. It was common, albeit legally dubious, for royal administrators to draw an income from one or more church jobs while not actually being present to do the work. Stillington held more such positions than most. Henry VI’s confessor William Aiscough, Cardinal Kemp, and the king himself all appointed him to these posts.
After the Battle of Northampton, the new Yorkist-dominated government appointed Stillington Keeper of the Privy Seal (one of the king’s chief ministers). He remained in this post for the first years of Edward IV’s reign. In June 1467 he was appointed Chancellor in place of George Neville, Archbishop of York. From 1458 he had been Dean of St Martin’s le Grand and he took refuge in his own sanctuary there during Henry VI’s readeption. (St Martin’s was one of the small number of sanctuaries, like Westminster Abbey, where people could take refuge indefinitely).
Stillington was restored to his position as Chancellor after Edward IV regained the throne but he was replaced in 1473 by the Bishop of Durham. Shortly after George Duke of Clarence’s trial, Stillington was arrested and imprisoned (27 February – 5 March 1478). This has prompted suggestions that he had been involved with Clarence’s designs on the throne. Stillington was pardoned in June and in the following year was acting as a royal ambassador.
In June 1483 it was probably Stillington who wrote the petition inviting Richard Duke of Gloucester to become king. At the beginning of Richard III’s parliament a bill was drawn up, called Titulus Regius, setting out Richard’s claim to the throne. This bill states that it contains the ‘tenor’ of the articles in that earlier petition. Records from shortly after Henry VII’s accession indicate that Stillington was believed to have been responsible for that bill.
Philippe de Commynes, writing in Henry VII’s reign, claimed that Stillington had personally provided the justification for Richard’s accession: he revealed that he had secretly performed a marriage ceremony between Edward IV and Lady Eleanor Butler before the king had married Elizabeth Woodville. This earlier marriage is commonly referred to as ‘the pre-contract’ and it meant that Edward’s marriage to Elizabeth Woodville was invalid and the king’s children were all illegitimate. Confusingly Commynes relates this twice in his memoirs and on the second occasion refers to Edward V being declared a bastard ‘under the colour’ of the bishop of Bath’s story. Commynes goes on to say that Richard had promised to allow the bishop’s bastard son to marry Elizabeth of York. It is difficult to know what to believe from this account and no other source names Stillington as the originator of the pre-contract story.
Stillington actually received no traceable rewards from Richard for his service. Henry VII issued a warrant for his arrest on the very day he won the Battle of Bosworth. Stillington was imprisoned in York and deprived of the deanery of St Martin’s, but was allowed to remain a bishop. He was pardoned on 22 November 1485 on the grounds of his ill health. The following year Henry refused to allow Stillington to be questioned further.
Stillington seems to have been implicated in Lambert Simnel’s rebellion and tried to avoid arrest by taking refuge at Oxford University. He was imprisoned at Windsor for some months. He died in the spring of 1491 and was buried in Wells Cathedral.
You can find Richard III’s instructions to send the Calais garrison a copy of the petition for him to bcome king here at volume III page 29 of Richard III’s signet book.
You can explore the palace of the bishops of Bath and Wells here.
 Philippe de Commynes, Mémoires, ed. Joel Blanchard (2001), p. 465.