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Richard's reign (1189–1199)

When Richard became king in September 1189, he had already declared his intention of joining the Third Crusade. He set about raising the huge sums of money required for this expedition through the sale of lands, titles and appointments, and attempted to ensure that he would not face a revolt while away from his empire. John was made Count of Mortain, was married to the wealthy Isabella of Gloucester, and was given valuable lands in Lancaster and the counties of Cornwall, Derby, Devon, Dorset, Nottingham and Somerset, all with the aim of buying his loyalty to Richard whilst the King was on crusade. Richard retained royal control of key castles in these counties, thereby preventing John from accumulating too much military and political power. The King named his four-year-old nephew Arthur as his heir. In return, John promised not to visit England for the next three years, thereby in theory giving Richard adequate time to conduct a successful crusade and return from the Levant without fear of John seizing power. Richard left political authority in England—the post of justiciar—jointly in the hands of Bishop Hugh de Puiset and William de Mandeville, 3rd Earl of Essex, and made William Longchamp, the Bishop of Ely, his chancellor. Mandeville immediately died, and Longchamp took over as joint justiciar with Puiset, which would prove a less than satisfactory partnership. Eleanor, the queen mother, convinced Richard to allow John into England in his absence.

The political situation in England rapidly began to deteriorate. Longchamp refused to work with Puiset and became unpopular with the English nobility and clergy. John exploited this unpopularity to set himself up as an alternative ruler with his own royal court, complete with his own justiciar, chancellor and other royal posts, and was happy to be portrayed as an alternative regent, and possibly the next king. Armed conflict broke out between John and Longchamp, and by October 1191 Longchamp was isolated in the Tower of London with John in control of the city of London, thanks to promises John had made to the citizens in return for recognition as Richard's heir presumptive. At this point Walter of Coutances, the Archbishop of Rouen, returned to England, having been sent by Richard to restore order. John's position was undermined by Walter's relative popularity and by the news that Richard had married whilst in Cyprus, which presented the possibility that Richard would have legitimate children and heirs.

The political turmoil continued. John began to explore an alliance with King Philip II of France, who had returned from the crusade in late 1191. John hoped to acquire Normandy, Anjou and the other lands in France held by Richard in exchange for allying himself with Philip. John was persuaded not to pursue an alliance by his mother. Longchamp, who had left England after Walter's intervention, now returned, and argued that he had been wrongly removed as justiciar. John intervened, suppressing Longchamp's claims in return for promises of support from the royal administration, including a reaffirmation of his position as heir to the throne. When Richard still did not return from the crusade, John began to assert that his brother was dead or otherwise permanently lost. Richard had in fact been captured shortly before Christmas 1192, while en route to England, by Duke Leopold V of Austria and was handed over to Emperor Henry VI, who held him for ransom. John seized the opportunity and went to Paris, where he formed an alliance with Philip. He agreed to set aside his wife, Isabella of Gloucester, and marry Philip's sister, Alys, in exchange for Philip's support. Fighting broke out in England between forces loyal to Richard and those being gathered by John. John's military position was weak and he agreed to a truce; in early 1194 the King finally returned to England, and John's remaining forces surrendered. John retreated to Normandy, where Richard finally found him later that year. Richard declared that John—despite being 27 years old—was merely "a child who has had evil counsellors" and forgave him, but removed his lands with the exception of Ireland.

For the remaining years of Richard's reign, John supported his brother on the continent, apparently loyally. Richard's policy on the continent was to attempt to regain through steady, limited campaigns the castles he had lost to Philip II whilst on crusade. He allied himself with the leaders of Flanders, Boulogne and the Holy Roman Empire to apply pressure on Philip from Germany. In 1195 John successfully conducted a sudden attack and siege of Évreux castle, and subsequently managed the defences of Normandy against Philip. The following year, John seized the town of Gamaches and led a raiding party within 50 miles (80 km) of Paris, capturing the Bishop of Beauvais. In return for this service, Richard withdrew his malevolentia (ill-will) towards John, restored him to the county of Gloucestershire and made him again the Count of Mortain.