Christopher Dawson's Incomplete Trilogy of Church History

From The Catholic World Report comes this article by Dawson biographer Professor Bradley Birzer, about three of Christopher Dawson's great historical studies:

Although largely ignored in its day, Christopher Dawson’s Christendom trilogy is the masterwork of one of the 20th century’s greatest thinkers.

As it turned out, the Christendom trilogy served as the last great work of English-Welsh historian and man of letters Christopher Dawson (1889-1970). Sort of. The trilogy derived, originally, from lectures Dawson had delivered while teaching at Harvard University between 1958 and 1962. As desired, the Christendom trilogy would consist of The Formation of Christendom (1967); The Dividing of Christendom (1965); and The Return to Christian Unity. In the broad, each volume represented one of three great periods of the Christian world: the ancient-medieval nexus; the Reformation and Counter Reformation; and the Church in the age of democracy, nationalisms, and ideologies.

Though The Formation of Christendom is technically volume one of Christendom, it came out two years later than volume two, The Dividing of Christendom. The idea to publish the lectures as a trilogy came to Dawson in 1963. His publisher, Frank Sheed, readily agreed. The only question was whether to publish them separately as a three-part work or immediately as a three-volume set. Sheed wanted to get them out as soon as possible, as he hoped the books would serve as the basis of discussions for the Second Vatican Council (1962-1965). . . .

If you don't recognize the title of the third book in the trilogy, that's okay: it never has appeared in print:

Unpublished, the only manuscript of the conclusion to the trilogy—badly in need of proof-reading, editing, and organization—resides in the Harvard theological library. Parts of it appeared as articles in various American conservative periodicals in the 1960s. But only very small parts. Someday, perhaps, a publisher might purchase the rights and release it properly. Until then, we must rest content with what Dawson left us.

And Dawson left us a very rich inheritance, indeed.

Perhaps Professor Birzer is the right man for the job of "proof-reading, editing, and organization" the manuscript of The Return to Christian Unity needs--and Ignatius Press the right publisher to "purchase the rights and release it properly"!