Judas hears that the Romans are brave and people love them and are flocking to join their army and they even went to Spain one time. Oh, and they fought Antiochus with a hundred elephants and took him hostage and now he has to pay tribute to them. Also, they took his best country and gave it to another king. And they took a bunch of his army's wives and children away and spoiled them (v. 10) which I'm thinking means 'raped and murdered' as opposed to 'gave them so much ice cream they wouldn't eat anything else.'
However, the Romans are nice to their friends, and they don't have a king who dresses in purple. Instead they have a senate and a president and there is no envy among them. He likes what he hears, so Judas appoints someone named Eupolemus to be his envoy to Rome.
Eupolemus is admitted to the senate and explains his mission. The Romans like him and they send him home with a letter of alliance and promising to write to Demetrius to complain about his treatment of the Jews.
Demetrius hears what happened to his last army and sends another. This time Judas' army is afraid and when the battle starts he only has 800 men. We don't know where the Romans are after their treaty. He tries to rally them, but they just want to go home. There's no real resolution, the next verse just tells us there was a fight and Judas is finally killed. His brothers bury him. Pretty quickly a new crop of evil leaders pops up. Also, and perhaps coincidentally, there's a famine, which causes revolts. The leaders blame Judas and go looking for his followers. Deservedly so, as they have gone to his brother Jonathan to complain about the lack of powerful Jewish leaders and ask him to take over.
Jonathan agrees and immediately the governor of Israel attacks him. So he heads for the wilderness, where the Greeks follow, planning to attack on the sabbath. Jonathan sends his brother John to pray with some friendly clans, but he gets kidnapped by the children of Jambri. They send word to Jonathan that one of their princes has made a great match with a Canaanite girl. So Jonathan and his friends go up into the hills to watch the wedding, then attack just as the dancing is getting going, which seems like a major faux pas, as it ruins the wedding.
Jonathan and his company go back to the wilderness and get attacked by the Greeks on the sabbath. They fight for awhile, then swim across the River Jordan after killing a thousand enemy soldiers. Bacchides, the Greek general, returns to Jerusalem and reinforces his walled cities. He also kidnaps some clan leaders' sons
As this is happening, another prominent Greek named Alcimus has the temple wall torn down. As it's happening, he's struck with a palsy and dies because his mouth is paralysed. Bacchides leaves for Greece. There's peace for two years, so Jonathan's enemies decide they've lulled him into a false sense of security and decide to bring Baccides back in a higher capacity, which leads to Jonathan killing fifty of them and going back to the wilderness.
Bacchides figures out where they are and attacks, but they leave and start smiting a new lot of people. And then they kills some more people and finally they send an ambassador to make peace. This time it's successful and Jonathan settles down to be the king.