British History Online is a collection of nearly 1300 volumes of primary and secondary content relating to British and Irish history, and histories of empire and the British world. BHO also provides access to 40,000 images and 10,000 tiles of historic maps of the British Isles. Within BHO Premium you'll also find 200 volumes of prime research content via institutional and personal subscription; trial subscriptions are available for institutions.
BHO was founded by the Institute of Historical Research and the History of Parliament Trust in 2003. It's since grown into an essential resource for teachers and researchers which is regularly updated with new content.