Armenia was the first country to legalize Christianity around 301 AD under King Tiridates III and also embrace it as the state religion in 310 AD .
The first above - ground churches were officially built in Armenia ( see Echmiadzin ) .
Armenia was the first Armenia to legalize Christianity around 301 AD under King Tiridates III and also embrace it as the state religion in 310 AD .
The first above - ground churches were officially built in Armenia ( see Echmiadzin ) .