Xbox One owners can now download Games With Gold Xbox 360 games even if they don't have an Xbox 360.
How to Download Free Xbox 360 Games on Xbox One Without an Xbox 360
1. Click this link here to find out which Xbox 360 games are available for free this month.
2. Sign in to Xbox.Com with your registered Xbox Live GOLD Microsoft account.
3. Search for the Xbox 360 game that you would like to download to your Xbox One. One of the free Games with Gold games this month is DIRT 3. Search "Dirt 3". Click on the GAME "Dirt 3".
4. Now that you are on the Dirt 3 page on Xbox.com and logged in, you should see a Download to Xbox 360 button. Hit that..
That's it.. Give it a few minutes and then refresh your Xbox One QUEUE under My Games and Apps.