Jesus primarily did ministry in Galilee, He grew up in Nazareth and the Bible says that He had visited all the towns and villages of Galilee and taught in their synagogues. Part of the reason, I believe, He spent so much time there was that the people who lived there were passionate for God and for His return to Israel, they were eager for Him to kick the Romans out and to cleanse the Temple from the corrupted priesthood. The Galilee was in northern Israel with Samaria in the middle and Judea in the south. They lived here because they were a relatively new community in the first century who had just returned from the Babylonian exile in the Old Testament period. They stayed in Babylon when Nehemiah returned because they knew that they would still be under foreign oppression and they had a decent life in Babylon. When Judas Maccabeus led his resistance against the Seleucid oppressors in the first century B.C. the Jews in Babylon returned to fight and eventually settled to the north.
Over time the priesthood became influenced, as did most of the people on the known world, by Greek Hellenism. The priests morality became lax, they attended the Greek Gymnasium to watch the nude wrestling... It was frustrating to the Galileans who had just returned and found their spiritual leaders acting as bad as the pagans they had just helped kick out. At that time they resisted the priesthood with their words and their will to stay committed to God and His Torah. This was bad enough to them but it was about to get worse.
Soon the power of Rome would conquer the world and with it went Israel. The Roman rulers were friendly to the nations who did not fight their take over, the Hebrew people were one of these groups. Instead of ruling them with an iron fist, they allowed the priesthood to stay in power as long as they said prayers to their God on behalf of Caesar. They also put a King in power, King Herod, who would report back to Rome but for the most part ruled the people autonomously. This situation benefited the priests and they took full advantage of their power laying heavy taxes on the people while they lived rich lives, putting heavy burdens on the people spiritually and helping Rome stomp out any would be Messiahs. This became too much for many in the Galilee and would push their rebelliousness to the extreme and formed a sect of Judaism known as the Zealots. When before they rebelled with righteous living, now they used force taking any chance they would get to kill Romans, tax collectors, Sadducees, and priests. They went around with a six inch curved blade that they could conceal and would assist them in assassinating the enemy by approaching from behind and quickly slitting their throat or piercing their heart. Another common act of violence was to find a priest or Levite and cut off a part of their face, an ear, nose or eye. They did this because the Torah says that anyone who is missing a piece of their body was unfit to serve in the Temple.
It was from this sub-group of Israel that some prominent New Testament figures come from. We know of Simon the Zealot, who was called by Jesus to be one of His followers; Barabbas, the terrorist who was freed in place of Jesus; and even Judas Iscariot has links to this dangerous group.