You can find the full list on the separate Historical Primary Source Databases guide.
Note: Please keep in mind that we purchase/subscribe only to databases where the majority of sources are in English. This means that sources found here are most likely going to represent a British perspective.
If you are interested in British imperialism, we also have a number of small collections of British documents (part of the larger Archives Direct Collections) tied to specific regions. These can be found on the on my Historical Primary Sources Databases guide world page.