King Tiridates III of Armenia +
1Wikipedia.
URL = http://en.wikipedia.org/wiki/Tiridates_ III_ of_ Armenia.
"Tiridates III (spelled Trdat; 250-330) was the king of Arsacid Armenia (287-330), and is also known as Tiridates the Great; some scholars incorrectly refer to him as Tiridates IV as a result of the fact that Tiridates I of Armenia reigned twice). In 301, Tiridates proclaimed Christianity as the state religion of Armenia, making the Armenian kingdom the first state to embrace Christianity officially."