So, we left Richard II at Conwy Castle with maybe twenty supporters. Conwy (a.k.a. Conway) is a formidable stronghold, but at this period it was probably being run on a care and maintenance basis, with just a caretaking staff and maybe a few archers. It's highly unlikely that it was stuffed with food and weapons, and even more unlikely that it had much in the way of furnishing.
In other words, a fairly uncomfortable lodging. Although, as I mentioned in an earlier post, there were ships in the harbour and if Richard had had a grain of sense he would have climbed into one and sailed away. There is no disgrace in running away when you cannot win - see the career of Edward IV for details.
Instead he sent off Surrey and Exeter to Chester, where Bolingbroke promptly imprisoned them. (The fact Exeter was his brother-in-law apparently cut no ice whatsoever.) The Earl of Northumberland was sent to Conwy to talk terms.
Northumberland was a good choice in many ways. He had been a moderate during Richard's reign, siding (until now) neither with the King nor his extreme opponents.
The terms Northumberland offered were quite generous, on the face of it. Henry wanted his lands back and a parliament held over which he would preside as Steward of England. He wanted treason trials for Salisbury, Surrey and Exeter, the Bishop of Carlisle and Richard Maudelyn. (Richard Maudelyn was one of Richard II's clerks, and probably an illegitimate cousin, since he strongly resembled the King and was to act as his double. He may even have been Henry's brother as his mother appears to have been Katherine Swynford's waiting-woman, Hawise Maudelyn.)
As an aside, it's interesting that what might be called the 'York connection' was quite safe on this basis, neither Edward of York nor Thomas Despenser being named.
After a day or so of consideration, Richard agreed to accept the terms, and Northumberland swore an oath on the sacred Host that they would be fulfilled and Richard allowed to continue to reign. In view of subsequent events, I think it highly likely Nothumberland was sincere; it's hard to believe such a man would risk damning his soul for Bolingbroke's benefit.
In all fairness I must record that it appears Richard had no intention of keeping faith with Henry - he was swift to tell his companions there would be no parliament, that he would mobilise Wales, and he would have his enemies put to a shameful death. He probably thought that given a year or two he could regain his power in roughly the same way he had after the Appellant episode.
Anyway, they set off from Conwy, and a little way along the road came across the bulk of Northumberland's men, who had been left out of sight. Richard balked at this, and wanted to return to Conwy, but Northumberland said there was no need to question his honour and, according to one source, repeated his formal oath.
However, with Northumberland's men around him, Richard was now a prisoner.