The leader who used the Church to unify the German Kingdom was <u>Otto I</u>.
<h3>Who was Otto I?</h3>
Otto I was the Holy Roman Emperor who rules the German Kingdom from 962 until 973. He suppressed the rebellious vassals for consolidating the German Reich. He fought various battles after the Kingdom was under his control after his father Henry I. He was famous as the most powerful western European ruler.
He took victory over the Hungarians by using Church for unifying the Kingdom. This helped him to create a secure empire and also showed his cultural renaissance to the people of his Kingdom.
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It would be "<span>"c) the no-third-term rule" that is not an example of governance that developed by custom, since this was only implemented after FDR won an unprecedented number of terms as president of the United States. </span>
I would say a civil war or uprising.
Also black death/black plague.
