I've mentioned before I've started my fictional world off by looking at its system of government. I've also looked at its broadcast media to a certain extent though I am aware I could expand this and there could be future stories in that direction. But you could look at how people/beings earn their living, what industries do they have and if for any reason this is not an issue, why isn't it? How are basic needs met? Even the Vikings, renowned for raiding other countries, must have had a shipbuilding culture!
What do your people(s) eat and drink? Do they trade with other worlds to bring in what they can't grow or create? How did trade deals come about? Have they ever gone wrong and did this automatically lead to war? There are loads of possible stories answering these.
I do love asking myself questions when I'm outlining. I find it an effective way of working out ideas and testing my answers to see if they are likely to be strong enough.