The 91/2 x 63/4in (24 x 17cm) oil on copper drew out eight telephone bidders at Cirrencester last Friday but it came down to a competition between two bidders in the room.
The bidding started at £1000 and initially went up in increments of £100. The auctioneers would not disclose any information about the buyer.
The price breaks the previous record for any picture lot sold in this country outside London. It now stands second in the table of all-time provincial prices, behind the £2.6m set by the Yuan vase sold at Woolley & Wallis in July 2005.
The picture came from a family who are now non-resident in Britain but are regular clients of the auctioneers, and they appear to have been unaware that it actually might have been from the hand of the Dutch Master.
On the verso was an inscription in French relating to the title of the work, The Young Rembrandt as Democritus the Laughing Philosopher. There was also a monogram in the top left which the auctioneers thought might be the initials HL. There was also some overpainting on the face, which led to some speculation as to the degree of Rembrandt's personal involvement with the portrait.
The £2.2m price breaks the previous record for a picture lot sold outside London which had stood at £1.7m for the Fra Angelico panels sold by Duke's of Dorchester in April earlier this year.
