What is the interaction of SEO and content marketing?
SEO is still mostly link driven.
If your site has powerful backlinks, it will rank. If it doesn’t, it won’t.
Good content + promotion of that content can result in great links, and that’s the relationship between the two.
Good content without links will still have some positive signals that Google picks up on (high page engagement, low bounce rate, lots of content) and that has a small impact on SEO.
But when people say “content is king” in SEO, they are indirectly saying that good content attracts good links, and good links are what drive SEO.