Was that Howard Phillips...

...Lovecraft (writer and inventor of HP sauce) in episode 'The Tall Grass'?

There's a vague resemblance, and the time period seems right.

I understood the episode as him witnessing some otherworldly phenomenon that would later inspire him to write his cosmic horror Great Ancient stories. He's advised not to tell anyone about what he's seen because no one will believe him anyway, so he writes about it like it's fiction...