So what is an evangelical, for the love of God, and why does it even matter? The answer requires an understanding of both the history and theology of the movement.

The term evangelical derives from the Greek word euangelion meaning “gospel” or “good news.” Technically speaking, evangelical refers to a person, church, or organization that is committed to the Christian gospel message that Jesus Christ is the savior of humanity. The Greek root word is used in the New Testament and was popularized in the first centuries A.D. to distinguish the love-centric movement of Jesus followers from the violent Roman Empire that often made its own “good news” announcements to celebrate military victories.

But words are more than their etymologies and dictionary definitions. They carry connotations with them too, which change over time and across geographies as they are used in different ways and settings.

According to the Institute for the Study of American Evangelicals at Wheaton College outside of Chicago, Martin Luther first used the Latinized form of the word evangelium to describe the non-Catholic churches birthed by the Protestant Reformation in the 1500s.

But the term largely took hold in the English-speaking world more than a century later during the Great Awakening, a series of revivals in Britain and the American colonies led by fiery preachers such as Jonathan Edwards and George Whitfield. Due to their influence, evangelicalism became a synonym for revivalism, or a fervent expression of Christianity marked by an emphasis on converting outsiders. By the early 1800s, it was “by far the dominant expression of Christianity” in the United States.

In some ways, Christianity took a beating in the early 1900s in America. The carnage of two World Wars and a Great Depression raised questions about whether God existed, and if so, whether God was both powerful and good. And modern science raised doubts about the viability of Christianity’s explanations for the origins of life. Evangelical leaders spanning denominations contemplated forming an organization to represent what one pastor called “the unvoiced multitudes,” and in 1942, the National Association of Evangelicals was born.

While the NAE couldn’t claim to be the sole or definitive voice speaking on evangelicals’ behalf, it helped redefine the term. According to Robert Wuthnow, the director of Princeton University’s Center for the Study of Religion and the author of Inventing American Religion, the de facto definition for evangelical was any person who belonged to a church aligned with the 40-odd denominations under the NAE’s umbrella.

But in 1976, the term went mainstream when a peanut farmer named Jimmy Carter won the Democratic primary and then the general election. He became the first U.S. President to call himself a “born again” evangelical Christian. Pundits scrambled to understand who evangelicals were and how many existed. Newsweek ran a cover story declaring 1976 the “year of the evangelical.”