The Open Conspiracy was Wells' Blue Print for A World Revolution; he regarded this book as his finished statement on the way the world ought to be ordered. Possibly he underestimated, or ignored, the fact that it is often in the interest of subsets of the human race to act against other subsets. Moreover the emphasis on religion seems odd, from a rationalist.

After the First World War, observing the lack of knowledge of most people about most things, he turned to history, starting, in 1918, his Outline of History first published in parts with 'gorgeous' covers, then in 1920 as a two-volume work including colour plates of a lavish nature for the time. In effect it was jointly authored — his chapters were sent to collaborators, and the resulting multiple corrections reassembled by the duly-chastened Wells. A 'popular' one-volume edition appeared in 1930. By the standards of its time this was a best-seller. It was praised decades later by A.J.P. Taylor as 'still the best introduction to history'. Toynbee had a favourable opinion of it. During the 1920s it sparked a controversy with Hilaire Belloc, who believed in such things as the 'Fall of Man'. It was also attacked by a teacher of Greek. Wells' hopes that school history could be taught in an international sense still, of course, have not come to fruition.

He planned and collaborated a hefty set of volumes on biology, The Science of Life, with his own son, and with Julian Huxley; the theme was largely evolutionary ( The Origin of Species was published only a few years before his birth). Huxley, a descendant of T.H. Huxley, regarded Wells as something of a Cockney upstart.

And he wrote a descriptive, rather than analytical, book on economics, which includes many ingenious observations but was eclipsed by Keynes' General Theory of four years later.

Some of his books were filmed; his Invisible Man was turned into a filmscript by Preston Sturges, who however regarded his books as not very filmable and infuriated Wells by making the invisible man mad. Another media incident was Orson Welles' radio broadcast of War of the Worlds in 1938, involving aggressive Martians landing in a location Americanised from its original Surrey, and which was reported to have cause mass panic among less educated Americans on the eastern seaboard.

C.P. Snow wrote of Wells that he could 'throw out a phrase that crystallised a whole argument', and that he 'never heard anyone remotely in the same class.' Among these phrases were 'the War that will end War', coined when he worked with the Ministry of Propaganda under Northcliffe during the First World War, which he supported, and 'the New World Order', which he seemed to be the first to use, or popularise, in a 1940 book of that title. His less successful phrases included the 'competent receiver'. He said of himself that he 'worked all the time'.

He was a socialist of an empirical, rather vague, rationalist type, disliking Marx and unenthusiastic about the managerial socialism of the Webbs.

His book The Open Conspiracy was published in 1928, subtitled Blue Prints for a World Revolution. Bertrand Russell said of this book '…I do not know of anything with which I agree more entirely' though since this was in a begging letter perhaps he was just being polite. It was revised and republished as What Are We to Do with Our Lives? in 1931.

In this short book, Wells attempts to answer the question: What should socialists actually do? — to which he confessed several times to having no very clear idea. It's a counter to Marx: why shouldn't non-proletarians unite to change the world?