(CNN)Before Turkey released American pastor Andrew Brunson, he was at the center of tensions between the two NATO allies.
To Turkey, Brunson was a spy who attempted to overthrow the government during a 2016 coup attempt. But to US officials, he was an innocent Christian family man who was wrongfully detained.
The debate strained relations between the two nations and raised the possibility of significant sanctions and further threats. So who exactly is Brunson, and how did the pastor become a key figure in US-Turkey relations?