Back in the day, when Leman Russ was an Imperial Guard general and when marines came with beaks, I created my own chapter of Space Marines. They weren't much more than a colour scheme (blue and yellow) and a name - The Custodians - which sounded cool because it seemed like they were in charge of guarding something - I never really thought what.
Well, that army played a few games before sitting in a box for twenty or so years, and then getting taken out to sell on ebay about 3 years ago.