Both content and backlinks are important, and their relationship is very close.
One thing to remember however. If your content is crappy, you are highly unlikely to rank well in Google anymore. You will not obtain any decent natural links, (why would anyone share or post a link to rubbish content?) and if you go out and create your own links, these will probably be seen as sub-standard links by Google anyway.
So in short, a successful website has to start with great content. This has to be the root of your web presence.
You then aim to get that content seen, shared and linked too, through spending time on your content marketing / social media strategies.
So quality content first, in order to EARN natural powerful backlinks.
And one thing to consider. Keyword research and long tail search terms can go a long way. If you focus on creating content that really is original, solves people's problems and adds value to the web in ways that other content in the same niche is not doing, you can find yourself ranking highly for that piece of content with very few links.