The Belleville, Ill., bishop had served as the vice president of the U.S. Conference of Catholic Bishops. The organization's vice president traditionally ascends to the top office.
Black Catholics see Gregory's election as recognition they have long sought from church leaders. Estimates of the number of black Catholics range from 2 million to 3.5 million, out of 63.7 million church members nationwide.
"It's a symbol of pride," said Richard Mark, who is black and the chief executive of St. Mary's Hospital in Gregory's diocese. "He shows that with intelligence, education and hard work, you can rise to the top ranks in whatever field you go into."
The 53-year-old Chicago native was ordained in 1973 and later earned a doctorate in sacred liturgy from the Pontifical Liturgical Institute in Rome. He became a bishop in 1983, serving for 10 years as auxiliary bishop under the late Cardinal Joseph Bernardin in Chicago.
He was installed as Belleville's bishop seven years ago. The diocese of about 105,000 Catholics covers a wide section of southern Illinois, including farming communities and the poor, predominantly black city of East St. Louis.
"I think it's important in a poor community like East St. Louis, where there aren't many role models, to have an African-American bishop," Mark said. "Many youths in East St. Louis have never seen an African-American priest, let alone an African-American bishop."
Gregory is known as a compelling speaker who frankly discusses racism as a sin he feels the church should do more to address. He has also written extensively on the church's opposition to the death penalty and physician-assisted suicide.
The election comes as the bishops are reviewing their position on the war on terrorism, acknowledging in a draft document a moral right to a military defense but warning that force alone is not the answer.
The authors of the proposed statement took pains to say that nothing justifies terrorism. Still, they argued that poverty, violence and human rights abuses, if not addressed, generate resentment that terrorists can exploit.
The proclamation urges U.S. leaders to redefine foreign policy to make alleviating global suffering a priority, and recommends lifting economic sanctions against Iraq and helping to end the Israeli-Palestinian conflict. It also asks national leaders to develop criteria for when the airstrikes on Afghanistan should end.
The bishops will vote on the proclamation by the end of their meeting Thursday.
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