James Ogilvie served throughout the Peninsular War firstly as Assistant, and from 22 March 1812 Deputy Commissary General, and the greater part of the collection relates to this period. It consists of: letters from, and statistical and other returns, vouchers, accounts and other financial papers submitted by, junior officers and clerks of the Commissariat Department; Ogilvie’s letters to the Commissaries General Sir Robert H Kennedy, Sir Charles Dalrymple and Thomas Dunmore, with their replies written in the outer columns of the same sheets; letters from serving officers in the various regiments on active service; and letters and papers from Portuguese and Spanish officials, and later, from French merchants and traders. There are also letters and papers from Treasury officials and some Commissariat officers, together with drafts of some of Ogilvie's replies, written at various times after the war, from 1816 to 1828, in attempts to settle the Commissariat accounts, some of which were outstanding from 1811.

In addition, there is a substantial unrelated miscellany (probably incomplete) of accounts and other financial papers, together with some correspondence, 1794-1815, of Richard Hely Hutchinson, 1st Earl of Donoughmore, relating to recruiting for and provisioning the 94th and 112th Regiments (which were reduced in 1795). Most of these items are dated between 1794 and 1797: several of them are copies made apparently in or about 1811; and all appear to be connected with Donoughmore's efforts to have his expenses reimbursed.