What kind of king and kingdom?
The disciples and people of Jesus day were taught that the Messiah would be like a conquering king like Solomon that would free them from the rule of the Romans and establish Israel as a great kingdom. That is what they were expecting. I really think that is what attracted Judas Iscariot in the first place. He was the treasurer of the disciples money in Jesus' day and probably had hopes that he would be put in charge of the entire kingdom's money when Jesus came into power (John 12:6). He was expecting a conquering king because of some of the Old Testament language that refers to Jesus as a king, but he didn't understand God's timing or plan. Jesus himself affirmed that he is a king. In John 18:36 it says that Jesus said "My kingdom is not of this world. If My kingdom were of this world, then My servants would be fighting, that I might not be delivered up to the Jews; but as it is, My kingdom is not of this realm." If you notice how many times