When starting a greenfield project, the programming language will affect the culture quite a bit. At such a project, I chose C# because it's a reasonably good language and easy to hire for. What I found was that there's a culture of writing—in my opinion—overly abstract code. Our coding challenge could be solved easily in 50 lines of code, but most candidates would submit huge projects with dependency injection, type reflection, class hierarchies, etc. It was hard to create a culture of simplicity.

Now, this is highly subjective, but I think the general lesson applies: Programming language choice is important for culture.