Kroonisten

I’m not familiar with a widely recognized topic called “kroonisten.” Could you clarify what you have in mind? Specifically:

- Which language or country is the term from (for example Dutch, Estonian, Finnish, etc.)?

- Is it a historical group, a political/religious movement, a cultural term, or something from fiction?

- Any time period or key facts you want included?

Once I have that, I can draft a concise, neutral Wikipedia-style article of under 300 words.