Awesome idea! Can I add a suggestion? The UK's House of Lords also has Lords Spiritual. I think the ASB can have the same. I think the Chiefly Council should include a few bishops, both Catholic and Angican and one of those Swedish Lutheran Bishops. A gazillion bonus points for somebody who can find a way for a Bishop-Prince to be there too. And because this is in America, there should be presidents of other churches (like Methodist, Baptist, and Mormon) so they don't feel left out. I can see a modern ASB adding leaders of black churches into the mix. And maybe a couple prominent rabbis and during a radical phase even a witch or pagan leader.
So... hm. My first thought was no, that's too weird, no way. On the other hand, looking back at the origins of the Chiefly Council, there definitely were religious leaders, mostly missionaries, who participated in the earlier Grand Councils. I had assumed that these types simply stopped participating as the ASB's institutions evolved into a modern government. I don't know, somehow the Chiefly Council doesn't seem quite right, either. It's not simply an imitation of the House of Lords, after all. Would it make sense for religious leaders to have their own, yet another body? Sort of a First Estate whose role ends up being ecumenical relations.
You know, the more I think about it, the more I like the idea of some kind of "established pluralism". It fits the culture of the ASB - I have certainly written a lot about religion. And some states have a history of Establishment. Carolina's government *was* explicitly modeled on England's, and Anglican bishops had seats in the upper house until 1903. Labrador, too, had Moravian clergy participate in the government until the 20th century. ... I also think I lean more toward giving them their own separate body rather than make them members of the CC, but there I'm not 100% sure.
I'd like to revisit this. I really do like the idea of a not-quite-government council for religious leaders, similar in status and role to the Chiefly Council. I haven't written anything about it, at least partly because I can't think of a good name for it. Council of Churches gives the wrong impression. But I have a general idea of how it works.
The Grand Councils grew out of the succession of meetings between the French and allied Indian leaders; the Great Peace of Montreal in 1701 is the archetype, and as the councils grew and became more regular, missionaries and later bishops were definitely involved. In the late 1700s and early 1800s, the Grand Council emerged as a body for wider diplomacy. Religious leaders who attended now included the bishop of San Agustín, Moravian missionaries, and Anglican prelates from the Loyalist states. The head of the Lutheran church in Christiana may have also been involved.
By 1820 the Grand Council was one of the key institutions of the confederation. While the Congress represented the state governments, and the Parliament would eventually represent the people, the Grand Council represented the permanence of the alliance itself. It was assuming a role as the guardian of the confederal constitution. Congress was kept busy with the day-to-day work of managing confederal affairs, but the Grand Council dealt with the major questions of how to interpret treaties, resolve borders, and share power. In 1865 it took on the responsibility for foreign affairs when it negotiated a treaty with England.
This was a lot of power to be taking on, so there were calls to regularize the Council's membership. A motley gathering of leaders was fine when the members were tribal societies and paternalistic colonies, but now they were states. They needed clearer rules about who was to govern. In 1836, at the urging of republican states, the Council removed all members who participated as holders of hereditary titles, forming them into the powerless Chiefly Council. An increasing work load meant that other
ex officio members were also dropped. Heads of state governments ceased to be Council members in the 1840s, since they no longer had the time. To replace them, the Council delegated to Congress the power to choose elder statesmen from the various states to sit on the Council full time.
For a long time though, the clergy stayed around. The republics largely had disestablished whatever state churches they had had, but they did not find the clergy to be as inherently offensive as the hereditary chiefs. Even the reforms of the 1870s, in which Parliament took from Congress the power to name Council members, did not touch them. The real problem came to be not necessarily the separation of church and state, but the growing size and diversity of the population. Bishops and church leaders multiplied, but the Grand Council was reluctant to just admit multitudes of clergy to its ranks. It was starting to look very anachronistic to have just a few religious leaders who just happened to hold seats that were historically important. On the other hand, it was considered worthwhile to have a national forum to foster religious pluralism and dialogue. Therefore, a new religious council was created in 1882 for this purpose, and the remaining religious left the Grand Council. Subsequent reforms removed the last remaining ex officio members, leaving only the Parliament-appointed members.
The new council was modeled on the Chiefly Council: a body that was not part of government but was nonetheless near it, at the heart of the ASB. Unlike the CC, it does receive modest tax support to fund its activities, things like travel and publishing. Its role is often described as "established pluralism": harmony among the different religions is as much part of the ASB's mission as is harmony among the states. Its members include leaders from across the ASB's religious spectrum, including the non-Christian religions that have grown with modern immigration. Revivalist indigenous faiths have won a place as well.
Anticlericalism has been a force at various times and places in the ASB, so there have been calls to defund or abolish this tax supported religious body. It hasn't happened yet, but funding has dropped quite low under some administrations. Also, the existence of the council has encouraged the existance of organized humanist or freethinker societies, which have representation.
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There are some wrinkles in this scheme. Difficult questions include: How to give a voice to unorganized expressions of Boreoamerican religion? These include both indigenous faiths and African diaspora faiths like Vodou and Santería. How to distinguish these authentic expressions from kooky new cults and nonserious religions - your Jedi, your Satanists, your Universal Life Churches - which are no doubt always clamoring for inclusion? One thing that the members don't want is to be constantly bogged down in debates over who gets a seat at the table. That's not why they're there and it's not what they signed up for. The most sensible thing would be to have a committee on membership and have everyone else agree to keep membership debates to a minimum outside that committee.
This also leads to much broader questions about those unorganized and less-organized religions. The Indians in TTL converted to Christianity in large numbers to the point where conversion was considered the norm. But unlike in Spanish America, this conversion was never forced, and Indians who were skeptical of Christianity or loyal to the old traditions did not face the same pressure to disguise their practices. So conversion was widespread, and certainly there has been that thing where indigenous customs persist in a Christian guise, but it was not 100%. Native religion survived in pockets throughout the Indian states. The more recent change, since 1900 or so, has been a series of attempts to organize these disparate groups in some way to give them more visibility and coherence. I can't say yet exactly what that looks like.
The African diaspora religions are a still different story, because, originating in a context of slavery, they were actively suppressed throughout history. Many people, including many practitioners, consider them to be nothing more than witchcraft or deviant Catholicism. Like in OTL, it is only recently that there has been an awareness of them as distinct religious traditions. Compared to OTL. I imagine that they are more widespread in continental North America, including in some parts of the Anglophone states like the Bahamas and southeastern Carolina.