British Unitarianism came from many different sources. The source of much Unitarianism was the old Presbyterian churches dating back to the Great Ejection in 1662 , over the years these churches became increasinly liberal until they became Unitarian. Although Presbyterianism was the dominant strand, other movements did come into the Unitarian community. Unitarians came from Anglicanism ( Lindsey ), Methodist Unitarianism and the General Baptists. But these remained a minority that were absorbed into the majority. Well what's that all got to do with anything? Well it means that the style (but not the polity) of Unitarianism is dominantly Presbyterian. And what can we say about Presbyterianism in the last few decades in the West? It's in decline. It's in a nose dive. The United Reform Church has halved it's membership since 1972. The Presbyterian Church USA is losing 50,000 members a year . Liberal-moderate Protestantism is dying. I think this is largely about worship.