Sullivan, whose CV includes stints at Petrus, London, with Marcus Wareing and the Wheatleigh hotel in Lenox, Massachusetts, USA, has most recently worked as a consultant chef in the Cotswolds and as senior sous chef at the Montpellier Chapter, Cheltenham.
He said he is "thrilled" to be joining the team at the Grade-II-listed King's Head, which has been closed since 2007 and is due to reopen in the summer following a multi-million pound refurbishment.
"The dynamic vision of the team behind the opening is immense," he said. "The interiors coupled with the overall concept will result in a hotel like no other in the Cotswolds. My aim is to put the Kings Head on the culinary map and to build an excellent reputation within the town and furthermore, the Cotswolds itself."
Working alongside the Vineyard Group's Michelin-starred executive chef Daniel Galmiche, Sullivan will lead the kitchen brigade and manage all aspects of the hotel's food and beverage operations. He joins the hotel's general manager, Stephen Mannock, who was previously general manager of the training hotel Wivenhoe House in Colchester, Essex.
As well as owning two hotels near Newbury, Berkshire - the Vineyard and Donnington Valley - the Vineyard Group has previously managed Sonoma Hotels, which included the Barns hotel in Bedford and Brownsover Hall hotel in Rugby, as well as properties in Edinburgh, Paris and the Lake District.