Complex sentence: The first magazine to be primarily associated with fantasy and science fiction was "Weird Tales", and its first issue appeared in March 1923, edited by Edwin Baird, and published by Rural Publications, a company owned by Jacob Clark Henneberger and J.M. Lansinger.
Split into simpler sentences: The first magazine to be primarily associated with fantasy and science fiction was "Weird Tales", which appeared in March 1923. It was edited by Edwin Baird and published by Rural Publications, a company owned by Jacob Clark Henneberger and J.M. Lansinger.