Robbie Williams serenades the stars at billionaire JP's secret celebration for McCoy

The billionaire has long held the title of party king - but last week, his latest in a series of extravagant bashes, this time to celebrate the career of jockey AP McCoy, was the jewel in the crown.

With 2,000 special guests and celebrities flying in from around the globe to the five-star Adare Manor to mix with those from the locality, the community received a much-needed boost.

Her Royal Highness Princess Anne and billionaires Dermot Desmond and Denis O'Brien mixed with locals involved in GAA, in McManus' scholarship fund, as well as business owners at the party which went on from 6pm until 6.30am.

Ireland's past and present political leaders were also out en masse. The guest list read like a "who's who" of politics, covering a range of parties.

The old guard, including Bertie Ahern, Charlie McCreevey and Mary Harney, joined Leo Varadkar, Jan O'Sullivan, Francis Fitzgerald, Simon Coveney, Michael Noonan, Willie O'Dea, Micheál Martin and Enda Kenny, who all attended the event along with the mayors of both Limerick city and county.

"It was so relaxed. Everyone was together, there was nobody kept away on their own. Everybody could meet anybody, from royalty to the peasants," joked one guest.

While most people arrived in a fleet of buses, others arrived by helicopter or were chauffeured by limousine.

But despite throwing the party of the decade, the unassuming host stayed quietly behind the scenes, leaving the speeches to his son, and the man of the night, AP McCoy.

"JP didn't speak, he wouldn't be into that. He left that to his son Kieran who said a few words and, of course, AP spoke," said one guest.

While champagne, Guinness and fine wine flowed, guests enjoyed a lavish meal, including prime rib of Golden Vale beef and wild Kerry salmon.

"There were several bars on each floor of the marquee but you didn't have to go near them. Everywhere you turned was a waiter or waitress wanting to get you whatever you wanted. From the moment you arrived, it was all taken care of and it was the best of everything," said a guest.

Sports stars, including Munster legends like Paul O'Connell, Peter Stringer, David Wallace and Jerry Flannery, also enjoyed the bash, as did Brian O'Driscoll with his wife, Amy Huberman. Former Westlife stars Nicky Byrne and Shane Filan were also present on the night.

The party was entertained by MC, BBC sports presenter Clare Balding, and a number of musicians before the main act. Ever the party host, McManus was delighted to keep the element of surprise with the sudden appearance of Robbie Williams delighting guests.

"Robbie Williams just arrived and did his set. Nobody knew he was coming in advance. He seemed to play for hours. It was a great night," they added.

But the highlight of the night was the crooner's encore, where he was joined on stage by the AP McCoy for Frank Sinatra's 'My Way'.

Despite throwing a party never to be forgotten, as always, businessman McManus requested discretion from guests and staff. Crews were working on the venue, including the multi-tiered marquee which is the biggest in Europe, for weeks in advance - but were sworn to secrecy. Staff were asked to leave their mobile phones at home. Guests also received notes, left on the seats of the many buses ferrying them in, kindly requesting that they did not share any photos taken on social media.

"There was no issue with bringing phones but they just didn't want the photos put up on the internet, there was a note on every seat on the bus... but it wasn't a big deal. The whole thing was just so relaxed, just a very big party," said a guest.

As guests were ferried back to the fully booked hotels around Limerick, each was presented with gifts. The event also proved a bumper pay day for local businesses. McManus sourced most of the produce locally.

"It was a big boost to the local community, he employed a lot of local bus companies. The catering, extra security and wait staff were all local.

"There were 2,000 guests but there must have been 2,000 locals involved in the sidelines, so it was a major event for the locality. There was a great buzz about it," said one guest.