Background: Richard of Bordeaux was the younger son of Edward, the Black Prince, and Joan of Kent. Edward, heir apparent to the throne of England, had distinguished himself as a military commander in the early phases of the Hundred Years' War, particularly in the Battle of Poitiers in 1356. After further military adventures, however, he contracted dysentery in Spain in 1370. He never fully recovered and had to return to England the next year.
Context: Whereas the poll tax of 1381 was the spark of the Peasants' Revolt, the root of the conflict lay in tensions between peasants and landowners precipitated by the economic and demographic consequences of the Black Death and subsequent outbreaks of the plague. The rebellion started in Kent and Essex in late May, and on 12 June, bands of peasants gathered at Blackheath near London under the leaders Wat Tyler, John Ball, and Jack Straw. John of Gaunt's Savoy Palace was burnt down. The Archbishop of Canterbury, Simon Sudbury, who was also Lord Chancellor, and the king's Lord High Treasurer, Robert Hales, were both killed by the rebels, who were demanding the complete abolition of serfdom. The king, sheltered within the Tower of London with his councillors, agreed that the Crown did not have the forces to disperse the rebels and that the only feasible option was to negotiate.  It is unclear how much Richard, who was still only fourteen years old, was involved in these deliberations, although historians have suggested that he was among the proponents of negotiations. The king set out by the River Thames on 13 June, but the large number of people thronging the banks at Greenwich made it impossible for him to land, forcing him to return to the Tower. The next day, Friday, 14 June, he set out by horse and met the rebels at Mile End. The king agreed to the rebels' demands, but this move only emboldened them; they continued their looting and killings. Richard met Wat Tyler again the next day at Smithfield and reiterated that the demands would be met, but the rebel leader was not convinced of the king's sincerity. The king's men grew restive, an altercation broke out, and William Walworth, the mayor of London, pulled Tyler down from his horse and killed him. The situation became tense once the rebels realised what had happened, but the king acted with calm resolve and, saying "I am your captain, follow me!", he led the mob away from the scene. Walworth meanwhile gathered a force to surround the peasant army, but the king granted clemency and allowed the rebels to disperse and return to their homes.  The king soon revoked the charters of freedom and pardon that he had granted, and as disturbances continued in other parts of the country, he personally went into Essex to suppress the rebellion. On 28 June at Billericay, he defeated the last rebels in a small skirmish and effectively ended the Peasants' Revolt. Despite his young age, Richard had shown great courage and determination in his handling of the rebellion. It is likely, though, that the events impressed upon him the dangers of disobedience and threats to royal authority, and helped shape the absolutist attitudes to kingship that would later prove fatal to his reign.
Question: when did the peasants revolt?

Answer:
the poll tax of 1381 was the spark of the Peasants' Revolt,