A loyal follower of the House of York during the Wars of the Roses, he became a close friend and one of the most important courtiers of King Edward IV, whom he served as Lord Chamberlain.

His importance in these years is recorded in a number of sources, and was recognised by the greatest peer in the realm, Richard Neville, Earl of Warwick.

Hastings raised troops for Edward in the English Midlands and served as one of the leading captains of the Yorkist forces at both Barnet and Tewkesbury.

His service, loyalty and ability, along with the fall of his Neville in-laws, made Hastings even more important during the second half of Edward IV's reign.

He was also appointed Lieutenant of Calais, which made him an important player in foreign affairs, and given authority over an increasingly large section of the English Midlands.

At court, he was involved in two lengthy feuds with members of Queen Elizabeth Woodville's family, most notably with her son Thomas Grey, first Marquess of Dorset.

The contemporary (1483) account of Dominic Mancini records Richard's claim that those who were arrested "had come with concealed weapons so that they could be the first to unleash a violent attack"; this was later confirmed in a public proclamation.

The traditional account, harking back to authors of the Tudor period, including William Shakespeare, considered the conspiracy charge invented and merely a convenient excuse to remove Lord Hastings, who was known for his loyalty to the dead King Edward IV and his heirs, as while he remained alive he would have been too formidable an obstacle to Richard's own plans to seize the throne.

[23] Several witnesses were present, hence a treason trial could have been conducted at an ad hoc Court of Chivalry convened by Richard as High Constable of England.

[24] Despite the accusation of treason, no attainder was issued against Lord Hastings which again suggests a trial by the Court of Chivalry which had no power to attaint.