first country to adopt christianity as state religion
Armenians Most Armenians adhere to the Armenian Apostolic Church, a non-Chalcedonian church, which is also the world's oldest national church. Christianity began to spread in Armenia soon after Jesus' death, due to the efforts of two of his apostles, St. Thaddeus and St. Bartholomew.[26] In the early 4th century, the Kingdom of Armenia became the first state to adopt Christianity as a state religion.[27]
Religion in the United States The majority of U.S. adults self-identify as Christians, while close to a quarter claim no religious affiliation.[2] According to a 2014 study by the Pew Research Center, 70.6% of the adult population identified themselves as Christians, with 46.5% professing attendance at a variety of churches that could be considered Protestant, and 20.8% professing Catholic beliefs. The same study says that other religions (including Judaism, Buddhism, Hinduism, and Islam) collectively make up about 6% of the population. According to a 2012 survey by the Pew forum, 36% of U.S. adults state that they attend services nearly every week or more.[3] According to a 2016 Gallup poll, Mississippi (with 63% of its adult population described as very religious, saying that religion is important to them and attending religious services almost every week) is the most religious state in the country, while New Hampshire (with only 20% of its adult population described as very religious) is the least religious state.[4]