The band played Johnny Cash and journalists put back pricey bar drinks and coffees, while elsewhere in Geneva's InterContinental Hotel the world's top diplomats – exhausted and eager to sign a historic deal on Iran's nuclear program – quarrelled and complained in the early hours of Sunday.
Here is a look at some of the more memorable behind-the-scenes details to emerge since the deal was announced.
'Ring of Fire'
Arguably the most surreal detail of the Geneva talks involves large hot-air balloons and a country folk band that were part of a charity ball being held on the same floor as the negotiations. At one point, as The Guardian's Julian Borger tells it in his account, negotiators were competing against a loud rendition of Johnny Cash's Ring of Fire.
The account also mentions diplomats hunting for food – the Iranians managing to find an Iranian restaurant nearby while other diplomats visited a pizza joint outside the hotel. The European Union's top diplomat, Catherine Ashton, apparently settled for bar snacks during breaks in marathon negotiations that were meant to wrap up on Friday but continued into the weekend.
According to Reuters, journalists waiting for word of a deal gathered in the hotel bar paying $9 for cappuccinos and $29 for Bloody Marys.
Last-minute bickering
It was bound to happen – a last-minute hiccup over the wording of the final text and attempts to insert changes in to the document that would be heralded as the most important agreement between Iran and world powers since the 1979 revolution, when relations between Iran and the West ruptured.
U.S. negotiators sent out a one-word e-mail – "DEAL" – to alert colleagues, only to have the Iranians seek changes to the final text minutes after all sides agreed on a deal, according to The Washington Post. "By then it was just too late. The deal was already done," an unnamed Western diplomat said.
The final hours of negotiations demonstrate how much uncertainty there was around a deal, as well as bickering and complaints. At midnight local Geneva time – still three hours from when the agreement was officially announced at 3 a.m. – a deal was far from certain, according to The Wall Street Journal.
In the intervening hours, tired diplomats, in their fifth day of talks, bickered and moaned. Iranian Foreign Minister Javad Zarif complained to U.S. Secretary of State John Kerry that Western negotiators were guilty of moving "the goal posts," the Post reported.
Backdoor entrances, service elevators
Before the Geneva agreement, the United States and Iran conducted parallel talks in secret – holding five meetings since last March – over Iran's nuclear program.
The news came to light only after the Geneva agreement was announced. The secret talks were largely kept from the United States' Western allies and friends in the Middle East.
The United States and Iran have been sworn enemies since the 1979 revolution so reaching an agreement between world powers and Iran meant that the two countries had to have some sort of prior understanding.
Leading the secret talks was U.S. Deputy Secretary of State William Burns along with the help of U.S. foreign policy adviser Jake Sullivan. According to The Associated Press, the exact locations of the meetings between U.S. and Iranian negotiators remain unclear.
But, as AP reports, the Obama administration went to great lengths to hide the role of Mr. Burns and Mr. Sullivan – leaving their names off the official delegation list attending the Geneva talks and having them enter the InterContinental from the back door and use a service elevator to attend negotiations.
Bitter friends
The United States has sought to reassure Israel and other friends in the Middle East – mainly Saudi Arabia – that the deal will make the region safer.
But feelings of betrayal run deep – and it comes down to the separate talks that the United States secretly held directly with Iran.
President Barack Obama reportedly informed Israeli Prime Minister Benjamin Netanyahu of the negotiations during a Sept. 30 meeting in the White House.
As it turns out, the Israelis already knew.
Speaking to BuzzFeed, an Israeli government minister said officials were aware that the United States was "going behind Israel's back" and that the Israelis were tipped off by a "friend in the Gulf" – reportedly Saudi Arabia.
The mainly Sunni Saudis have deep misgivings about the Iran nuclear deal – as well as Shia Iran's wider role in the region, whether it is supporting the al-Assad regime in Syria or what they see as meddling in Iraq and attempting to expand Iran's sphere of influence.
The House of Saud is also deeply unhappy about being left in the dark about the direct talks between the United States and Iran.
An adviser to the Saudi ambassador to Britain, Nawaf Obaid, told a London-based think tank that the United States had deceived one of its oldest regional allies. "We were lied to, things were hidden from us," Mr. Obaid said, according to The Telegraph. "The problem is not with the deal struck in Geneva but how it was done."
Twitter-plomacy
Whether it is Iran's Foreign Minister sending an undiplomatic tweet to his U.S. counterpart or Israel's Prime Minister taking to Twitter to warn world powers against signing a weak deal that would do little to curb Iran's controversial nuclear program, social media have been a go-to option for world leaders and diplomats.
It was no different when it came to the deal being announced.
"We have reached agreement between E3+3 and Iran," tweeted the spokesman for the European Union's policy chief, Catherine Ashton. The "E3+3" refers to the European nations of France, Britain and Germany plus the United States, China and Russia.
From Iran's Foreign Minister came this simple tweet: "We have reached an agreement."
Perhaps in a sign of how much relations between Iran and the United States have changed, Iran's President retweeted U.S. Secretary of State John Kerry shortly after the deal was made public.