The Corsini were a family of Florentine merchants based in the City of London in the sixteenth and seventeenth centuries headed by Filippo and Bartholomew Corsini. The Corsini Correspondence consisted of letters to the brothers Filippo and Bartholomew Corsini, addressed to their home in Gratious Street, in the City of London 1568-1601, from England, France, Germany, Brabant and the Netherlands, the Italian Duchies and States, the Republics of Venice and Ragusa, Poland, Portugal, Spain, Malta and Sao Tomé. There were also letters to Bartholomew Corsini in Firenze and Piacenza, 1600-1613.

The Corsini's business premises stood opposite St. Benet's Church on Gratious Street, at the crossroads formed by the junction of that street with Lombard and Fenchurch Streets.

Philatelist Robson Lowe (1905-1997) founded the Regent Stamp Company and subsidiary Robson Lowe Limited, a leading stamp auction house. Robson Lowe Limited was taken over by Christie's, the fine art auction house, in 1980.

In the 1970s Robson Lowe persuaded the Corsini family to sell their archive of correspondence, which contained letters of great importance for postal history. The merchants' considerable correspondence archive was sold by Christie's Robson Lowe at public auctions in September and October 1984, April 1985, June 1986, October 1988, and July 1989. As a result, some 3500 original letters have been dispersed, many to the hands of private collectors.

Fortunately, photocopies and microfilm copies of the correspondence were made at the time of the sales, and deposited with the City of London. The availability of these copies held by the London Metropolitan Archives has mitigated the adverse consequences of the splitting of the collection for sale (a common practice with auction houses and dealers) with regard to the integrity of the collection, and preserved knowledge of a key aspect of London's international trade in the Elizabethan and Jacobean period that would otherwise have been lost.

The Getty Research Institute also has 11 reels of microfilm copies of letters that were dispersed at auction in 1984-1986. The archive contains several hundred letters written to Filippo Corsini in London, and to other family members, by clients and family representatives throughout Western Europe. The Corsini firm, based in Tuscany, was a major international dealer in cloth and other commodities, and the early parts of the correspondence contain important information on textile manufacture and trade.

An interesting article about the Corsini correspondence is: Cox, Jacqueline The Corsini Letters 1567-1637, Journal of the Society of Archivists, Volume 9, 1988 - Issue 2. Published Online: 15 December 2009.