Ruth Williamson, 34, Margaret Whitehouse, 52, Peter Rowe, 60 from Britain, and Australian Andrew Thirsk, 35, were killed in a botched rescue attempt on 29 December.
Zein al-Abidine al-Mihdar - also known as Abu Hassan - the leader of the group, and the brothers Ahmed Mohammed Atif and Saad Mohammed Atif were charged with kidnapping when they were taken to a heavily guarded Yemeni court.
Far from denying the charge of kidnap, which carries the death penalty in Yemen, Mr Al-Mihdar shouted defiantly that his group had done everything in the name of God and that he had no regrets.
The Yemeni authorities were clearly nervous that some of the thousands of well-armed supporters that Mr Al-Mihdar claims to have would choose this moment to spring him from captivity.
The tiny Yemeni coastal town of Zinjibar had never seen such a display of security. In the bustling market place, where camels ambled past veiled women who sat around in the heat, uniformed police were spaced at 50-yard intervals.
Outside the courthouse, soldiers manned enormous Russian machine-guns on the backs of pick-up trucks. When the closed white van drew up with the three defendants inside, there was chaos as police tried to prevent photographs being taken. The men emerged, blinking in the harsh sunlight, before being jostled into the courtroom in handcuffs.
After brief formalities, the men were read their charges, which including executing a campaign of bombing, kidnapping and killing in southern Yemen.
No mention was made of the five Britons detained in Aden, whom the Yemeni government has been claiming are linked to the kidnappers. Yemen's ambassador has made clear that the five have not yet been charged, the Foreign Office said last night.
Mr Al-Mihdar then delivered a calm and terrifying diatribe in Arabic against the West, Christianity and rulers such as President Bill Clinton. He said he and his followers were trying to breach the blockade against Muslims by Britain, America, France and their allies. "Are we going to see the cross raised in this region," he asked the court rhetorically, "or the [Muslim] crescent? We are going to break the cross in this country and the same blood that was spilt in Afghanistan will be spilt against the Crusaders."
Smiling frequently as if the trial was all a game, Mr Al-Mihdar gave his blow-by-blow version of the shoot-out in which four of his hostages died and two were injured. He denied killing any himself, but freely admitted using them as human shields against the advancing government troops. "God sent them to us, so we took them," he said. "We kidnapped them to fight their countries because they don't believe in God or our Prophet."
Mr Al-Mihdar is clearly aware he has little chance of escaping execution and has even refused a defence lawyer. In the half-hour recess, he chatted amicably to journalists and even his government captors. We asked him if he knew the five Britons detained in Aden on suspicion of terrorism. He replied: "No." He also denied knowing the British radical Muslim cleric, Abu Hamza Al-Misri, who said this week that the kidnappers had called him last month.
Before the court adjourned until after the Eid al-Fitr religious holiday next week, the kidnappers' leader issued a call to his followers. "For those who are still at large," he said, "I hope they will continue the jihad against the Crusaders. May God strike you all."