Born in Tennessee into a rather poor family, Horace McCoy spent much of his youth employed in menial occupations, attempting to subsist through the Great Depression while reading voraciously and travelling as much as he could.
In 1920, he finally achieved his ambition of becoming a journalist, and although his frustration with the then-(relatively)-nascent media eventually motivated him to leave the industry, he spent a decade writing and working on some of his first attempts at fiction.
His short stories were well-recieved, and he soon moved on to novels, the most successful of which was They Shoot Horses, Don't They?, which was ultimately made into a movie.
After moving to Hollywood, McCoy embraced film as a more contemporary and effective form for personal and artistic expression. His terse style and gritty narrative ideas were quite appropriate for the movie industry of the time, and he worked on a number of scripts and screenplays.
I will add a complete list of his works as soon as I can find one...Sorry!