He was created because Friz Freleng needed a much more dangerous antagonist to be Bugs Bunny's enemy since Elmer Fudd was considered too soft.
He was also one of the members of a Looney Tunes team called the Tune Squad.
He is short man who is mostly evil, dangerous, grumpy, explosive, bad-tempered and loud, but sometimes has good intentions.
Sam quickly became just as hopeless as Elmer Fudd, though he is more dangerous and only a bit more smart than him.
Unlike Elmer, Sam does not fall for the same trick twice. He was even willing to shoot Santa if he doesn't give him any presents.
In Space Jam, he teamed up with other toons and Michael Jordan to defeat the Monstars.
In The Looney Tunes Show, he gives Bugs and Daffy advice to overcome everyday problems. He also comforts and hugs Daffy when he cried one time.
In Gribbler's Quest, he helped Daffy solve his problem with obsession with online shopping.