WHAT AND WHEN WAS THE FIRST MID SIZED PICK UP TRUCK?

My mothers boyfriend claims the Toyota Stout was the first MID SIZED truck EVER made. I am 31 and out of all the car trivia I ever came across I never heard this. WHO made the first mid sized truck and When was this made? I need proof as he is more hard headed than I am if I prove him wrong I need links...lol. Thank you so much old timers.