This is the bananal Island("banana field island") in northern Brasil, the largest purely fluvial island in the world (that is, an island that is only surrounded by river waters).

It's formed by the greatest fear of worldbuilders... A SPLIT RIVER

(Some other info in the comments)

Based on a conversation I had with u/_too_much_noise_ in the comment section of a post by u/No_Scientist1077, I decided to make a flowchart for people who struggle to decide what kind of government they want for their world or don't know the various kinds of government types there are.

The idea of the chart is that it will guide you towards a description of the state that best fits what you might be interested in or that it may lead you to a form of government you had not considered before. If some things are unclear, you want some more information or you want to discuss a government structure within your world hit me up!

I had seem issue getting the right way to make this flowchart, but I ended up making it with Word. I tried to get the quality as good as possible, but I don't know how it will look once I have posted it. I'm always interested in ideas for other ways to show this chart.

This chart is mostly about the government and ignores stuff like the state, the economy or the main ideologies of the state. If this post is useful to some people, I could post those as well. Please let me know.

Due to the success of this post, I decided to make a follow-up focusing on ideologies: https://www.reddit.com/r/worldbuilding/comments/1h4s6o7/resource_for_people_worldbuilding_ideologies/