Hector Protector was dressed all in green;
Hector Protector was sent to the Queen.
The Queen did not like him,
No more did the King;
So Hector Protector was sent back again.
This rhyme could have referred to Richard, Duke of York who was Protector of Ireland. He was called to England to take over the reigns of government when Henry VI could not govern. Henry's Queen, Catherine d'Anjou, disliked Richard, but had to deal with him until Henry was able to resume his duties.
Then Richard could be "sent back again".