For anyone in the UK (or those with access to a suitable VPN), there's an excellent programme on the history of photography available to watch on BBC iPlayer.
"Britain in Focus: A Photographic History" (presented by award-winning photographer Eamonn McCabe) is a mini-series of three one-hour episodes - parts 1 & 2 available to stream now; part 3 airs tomorrow evening on BBC Four, then available through iPlayer.
Part 1 examines the discovery of photography by Henry Fox Talbert and Louis Daguerre, and its development in 19th century Britain, including pioneering photographers Roger Fenton and Julia Margaret Cameron.
Part 2 looks at the emergence of photo-journalism in the early 20th century in relation to major events occurring at the time.
Part 3 covers the explosion of colour images in the late 1950s to the ongoing impact of the digital revolution.
I watched Part 1 last night and, whilst not as in-depth as a good book on the subject, it's a very enjoyable "potted history". Well worth watching