This page focuses on the literary classics published by Little Leather Library/Robert K Haas, which grew to over 100 titles. Not all titles are available in all bindings.
The chronology of literary classics published by the Little Leather Library can be somewhat pieced together by looking at their title lists over time. We see the list grow from 15 to 100. When adding together the titles from other series and special books that LLL/Robert K Haas published, such as the Holy Bible series, there is well over 150 unique titles. In general, it is easier to find title lists in the real leather LLL books and red leatherette miniature library books compared to other types. For example, it is rare to find one in a Redcroft Edition book. Not all books have title lists, but if they do, it can be found on the very back of the book.
It seems that only one title list has The Constitution of the League of Nations, and I have never seen one that has Constitution of the United States. The red leatherette miniature library books seem to have the largest amount of titles published (followed by the Redcroft Edition books), as many decisions were made during this time affecting which titles were published and how they were published. We see that The Jew, etc. by Ivan Turgenev was replaced with Mumu, etc. by Ivan Turgenev, making this a rare find. Idylls of the King Volumes 1 & 2 were both removed, and the titles Inferno by Dante, Confessions of an Opium Eater, Tales from Arabian Nights, and Words of Jesus each got split into two volumes.
One title list, First Fifty Titles, listed titles issued and titles not issued yet at the time, showing what they intended to print. While many were indeed printed, some have not been. Here is a list of what they once intended to print, but appear to have never done so, as these have never been found by collectors:
Among the titles marked already issued is Romance by Alexandre Dumas, but I have never seen this one, I'm unsure if it exists.
Below are some photos of title lists I've found. I've tried to put them in chronological order to the best of my knowledge. The 3rd version of the 60 title list lets the buyer choose between Genuine Sheep Leather for 30 cents or Red Imitation Leather for 15 cents.