Carl Rutter, 46, of Silcoates St, Wakefield, appeared on Monday 3rd June .
He will be sentenced alongside two other men in around four weeks time.
The fourteen items had been reported as stolen from three stately homes - Newby Hall and Sion Hill in North Yorkshire and Firle Place in Sussex. They have now been returned to their rightful owners.
They included a George III Pembroke Chippendale drop leaf table worth £500,000, and a pair of Louis XVI vases known as ‘The Firle Vases’ valued at £950,000.
Rutter was described as ‘a significant conspirator’ who had overall possession of a number of the stolen antiques which had been stored on his behalf with a view to being sold later.
Darren Webster, 45, of Burnshaw Mews, Leeds, and Brian Eaton, 69, of Chapel Road, Tankersley, Barnsley, also appeared in court in August 2012.
Both pleaded guilty to the same charges but have been awaiting sentence, subject to the outcome of Rutter’s court appearance this week.
Both Eaton and Webster had a large number of the antiques. Some were stored at Eaton’s home address.
But Webster was described by officers as the ‘lead conspirator’ whereas Eaton was responsible for introducing prospective antiques buyers to Webster and Rutter.
The valuables, known to be of significant and cultural historic value and worth a total of £5 million, were recovered by officers from the Yorkshire and Humber Regional Organised Crime Unit (ROCU) on 22nd September 2011.
It marked the culmination of a year long investigation carried out by the ROCU, supported by forces including South Yorkshire Police.
“We were immensely pleased and proud back in September 2011 to have recovered these high value antiques which were described as true pieces of British heritage,” said Det Supt Steve Waite, head of regional intelligence.
“Rutter’s guilty plea brings this absolutely fantastic case one step closer to its conclusion. It’s a great result for both the officers involved and the stately homes that were affected by these thefts.”