From the title, this sounds like it might be a legal treatise, but it's not. The subtitle is "Cardinal Mundelein and Chicago Catholicism," and it's really a biography of the former and history of the latter during the years George Mundelein served as archbishop of that archdiocese (February 1916 - October 1939).
I borrowed this book in the midst of research I was doing on a great-grandfather, because he is mentioned on two pages. I ended up reading the entire book, because it was so interesting and easy to read. Of particular note was a chapter called "Ethnic Tangle," describing the fascinating mix of typical "territorial" parishes organized on a geographic basis, and the existence at that time of numerous "national" parishes for non-English-speaking ethnic groups. For example, in one Chicago South Side neighborhood "roughly two miles long by a mile and a half wide, four territorial parishes staked out the corners of the neighborhood and served the English-speaking (largely Irish) Catholics. But this compact neighborhood also contained three Polish, two Italian, one Lithuanian, one Croatian, one Bohemian, and one German church as well."
I was especially grateful for the author's 47 pages of endnotes (after 241 pages of text), which led me to additional resources about my great-grandfather. There's also a seven-page index, a number of tables and maps, and a chronology.