Map History / History of Cartography. The Gateway to the subject. Lots of invaluable information on events, fellowships and prizes, map collecting and collections, online images of maps and much more. Includes sections entitled: Books to get you into the Subject; Web articles: People; Special topics: People; How to tell a fake or forgery, and much more.
History of Cartography Project. 'A research, editorial, and publishing venture drawing international attention to the history of maps and mapping'. The Project's major work, published by University of Chicago Press, is the multi-volume History of Cartography series [CUL classmark S696.b.079] some volumes of which are available online. 
See Also:
CUL Map Department's web pages
Cartography by Ken Field
Stanford Geospatial Center Extensive list of useful reading
Mapping, Society, and Technology by Steven Manson. University of Minnesota Libraries Publishing, 2017, from Open Textbook Library
mapschool Introduction to cartography