Conversation so far:
What was Immanuel Kant's political philosophy?
In Perpetual Peace: A Philosophical Sketch, Kant listed several conditions that he thought necessary for ending wars and creating a lasting peace.
What were Immanuel Kant's conditions?
Kant listed several conditions that he thought necessary for ending wars and creating lasting peace, which included a world of constitutional republics by establishment of political community.
What else did Immanuel Kant believe besides conditions that he thought were necessary for ending wars and creating a lasting peace?
He opposed democracy, which at his time meant direct democracy, believing that majority rule posed a threat to individual liberty.

Question: Were his beliefs controversial?
Self-contained rewrite: Were Immanuel Kant's beliefs controversial?