I finally got round to reading this rather interesting 1937 book and it was just as eye-opening as I was hoping for.
We need only look at last year's "The Mormon Candidate" documentary on the BBC to see how American the Church of Jesus Christ of Latter-day Saints is perceived as, especially in this country. To be fair, the LDS Church has often played on this as they've integrated into the American mainstream. But you'd be surprised, I think, if you know just how important the United Kingdom has been for the survival and continuation of the Church. And, perhaps more importantly, the Church has had a huge effect upon 10000s of British citizens and on communities across the country.
This book is written from the standpoint of a believer and is full of prose praising the Lord for all the wonderful things that helped spread the message in the UK. But if you can get around that you'll find A Century of Mormonism in Great Britain rather illuminating on the early work of Mormon missionaries in this country and of the rather amazing expansion of the Church (followed by an equally impressive emigration of believers to first Nauvoo and then to Salt Lake City).
At one point there were more Latter-day Saints in the UK than there were in the USA! Without the influx of British emigrants it is quite possible that Joseph Smith's church may have floundered as many believers began to apostasise (over allegations of polygamy and other doctrinal disputes). The British believers, having made a gigantic leap of faith in leaving their homes thousands of years ago were both more devout and less able to change their mind once they arrived.
It is no surprise that Utah now has the largest percentage of people claiming English descent in the United States.
This "American religion" turns out to be far more complicated than one might think. Certainly this book will help me continue to expand the Wiki article on the Church in the United Kingdom.