Name
- Lorenz, of the Austrian Consulate at Warsaw1
- Louis XVIII, of France1
- Maitland, James, 8th Earl of Lauderdale1
- Manners, John Henry, 5th Duke of Rutland1
- Mappes, Henry and Conrad, wine merchants, of Mainz and Hattenheim1
- Maria Elizabetha Francesca, wife of Reinhardt, Archduke of Austria1
- Marine Society1
- Martens, Baron? -, formerly Russian army officer; alias 'Mr. Miller'1
- Martin de Tyrac, Marie Louis Auguste, Vicomte de Marcellus1
- Mary, of Scotland1
- Matuszewicz, Andrey Jozef, Count1
- Meade, Richard Charles Francis Christian, 3rd Earl of Clanwilliam1
- Medem, Carl, of Neu Appussen, near Schranden1
- Merle, Gibbons, journalist1
- Mettemberg, Joseph, medical practitioner1
- Mitchell, John, of Add MS 472891
- Mocenigo, Georgii Dmitrievich, Count, Russian diplomatist1
- Moltke, Carl Emil, Count, Danish Minister in London1
- Montmorency-Laval, Anne Pierre Adrien, Duc de, French Ambassador in London1
- Moore, James Carrick, surgeon and author1