Carroll John Daly 
Knights of the Open Palm [EPUB ebook] 
Race Williams #1 (Black Mask)

The first hard-boiled detective Race Williams, runs up against the Klan in his premiere adventure, which leads him to fast and tragic action. Plus two other early Daly hard-boiled classics: 'The False Burton Combs’ and 'Dolly.’ Story #1 in the Race Williams series.
Carroll John Daly (1889–1958) was the creator of the first hard-boiled private eye story, predating Dashiell Hammett’s first Continental Op story by several months. Daly’s classic character, Race Williams, was one of the most popular fiction characters of the pulps, and the direct inspiration for Mickey Spillane’s Mike Hammer.