Since its founding more than two centuries ago, the Episcopal Church has often struggled to keep disparate factions unified under its diverse umbrella.
Repeated controversies -- over slavery, the ordination of women and even the role of children in church life -- have threatened to tear at its religious fabric.
Now, the church faces one of its most daunting challenges yet, with hundreds of conservative congregations forming a separate North American church amid a dispute with liberal Episcopalians over homosexuality and Scripture.
Presiding Bishop Katharine Jefferts Schori sees the latest discord in historical terms, a view that sheds light on Episcopalians' religious and cultural DNA.
Similar controversies have come and gone, she told Times reporters earlier this month, but the 2.4-million-member church has remained largely intact -- even if unity has sometimes come at a steep price.
"The place of gay and lesbian people in the church is the latest expression of the ancient human struggle over who is 'the other,' " Jefferts Schori said. "There will be another group. I don't know who it is going to be."
Slaves were one of these first "other" groups to cast a long shadow over the church.
During the Civil War the church held together loosely, as Methodists and other denominations split over the issue of slavery. Southern Episcopalians formed their own branch but were marked absent during the church's 1862 general convention, returning to the fold after the war.
The church may have emerged from slavery intact, but many contemporary Episcopalians believe it lost its moral compass along the way. Episcopal leaders, acting at their national convention in 2006, apologized for the church's "complicity" in slavery. Church officials also have acknowledged that Southern and Northern Episcopalians alike benefited from the slave trade.
Modern disputes have similarly engulfed the church. Its decision in 1976 to ordain women raised new tensions, prompting the departure of some congregations while transforming the Episcopalian landscape, ultimately leading to Jefferts Schori's election to the top church office.
Revisions to the Book of Common Prayer in 1979 led to further dissension. The changes made baptism more central to the practice of the faith, empowering lay people and challenging the historical power of the clergy. The updates also made the Eucharist a regular act of Sunday worship and allowed children to receive Communion before they were confirmed, further challenging established practice.
The struggle over homosexuality burst to the top of the grievance chart in 2003 when an openly gay priest, V. Gene Robinson, was consecrated as bishop of New Hampshire. Tensions mounted as local churches blessed same-sex couples even as the national church refused to authorize official rites for such ceremonies.
(As bishop of Nevada in 2003, Jefferts Schori voted to affirm Robinson's election. She also permitted congregations to bless same-sex unions if they chose to do so after discussing the issue and developing their own policies.)
In the time since Jefferts Schori's 2006 installation at Washington's soaring National Cathedral, the furor over Robinson and gay marriage has intensified. Conservative Anglican leaders from Africa and elsewhere have waged a revolt against what they see as a permissive American church.
Those who study the Episcopal Church say the recent tumult over sexuality exemplifies a deeply rooted tradition of religious freedom and tolerance that hearkens to the church's Anglican roots.
The American church, they say, grew up in the late 1700s as a democratic institution alongside a young American republic. As time passed, it remained part of the global Anglican Communion even as its policies and tone were influenced by the culture in which it matured.
"There is something in the Anglican ethos . . . in which we live out our life of faith in the messiness of everyday life," said the Rev. Ian T. Douglas, a professor at the Episcopal Divinity School in Cambridge, Mass.
Speaking of same-sex marriage, Douglas added: "If that's what we are wrestling with in American culture, then of course the Episcopal Church is going to wrestle with it."
Jefferts Schori believes that Episcopalians in general are far less preoccupied with issues of sexuality than the congregations that have broken away.
"In most of the rest of the church," she said, "people are moving on with feeding the hungry, providing housing for low-income people and doing creative things to build what we call the reign of God in their own communities."
The pressures within the Episcopal Church have amplified tensions in the Anglican Communion. Several of Jefferts Schori's conservative counterparts, meeting in Jerusalem last summer, called for the creation of a new independent church, and 700 breakaway congregations did just that this month, declaring themselves the Anglican Church in North America.
Scholars say Jefferts Schori, and the church she leads, must find a way to harmonize their differences in the same way their predecessors have done.
"The biggest challenge for the Episcopal church is to get over its own internal arguments to live out its identity as a church dedicated to God and its mission in the world," said Daniel Joslyn-Siemiatkoski, assistant professor of church history at Church Divinity School of the Pacific in Berkeley.
"The Anglican tradition is about holding things in a healthy and respectful tension and finding a way to . . . keep our eyes on the ministry we have been called to," he added.