The loose papers are mainly political, and the division between political and public and family and personal in their arrangement is very imprecise, with much of political interest to be found in the latter category.
The papers strongly reflect the 2nd earl's interest in parliamentary reform, from as early as 1792, his support for Catholic emancipation, and his enduring interest in foreign affairs. There is little political material, however, before 1800. Most of Grey's closest friends and political associates, such as Lord John Russell, Charles James Fox, Lord Holland, Lord Palmerston, Samuel Whitbread, etc. are well represented, as are foreign statesmen, foreign ambassadors in London, and British ambassadors abroad. There is also much of domestic interest, on topics as varied as vaccination, education, charitable matters, and family relationships.
The volumes are largely letter-books, mostly copy letters but including original letters of the 1st Earl of Durham to Grey as well as copies of Durham's despatches from St Petersburg to Palmerston.