Unitarian-Universalism is a uniquely
American flavour of Unitarianism - it is simply
Unitarianism in
Canada, where the number of
Universalist churches at the time of merging was very small, and in
central europe, the birthplace of
Unitarianism, and the rest of the world, separate from the UU merger that North America experienced, it remains Unitarianism. Still, the UUA, the north american (for now - the CUC, Canadian Unitarian Council, seeks to take on in Canada what has in the past been done by the UUA) Unitarian Universalist Association, exerts great influence on and support for the Unitarian movement worldwide.
The distinction between UU and Unitarian is mostly academic - modern unitarian/UU churches don't adhere to ANY set creed, including that of what have traditionally been known as unitarianism (the belief in the one-ness of god, the rejection of the trinity) or universalism (the belief that all beings will go to heaven, in a god of universal love). So the distinction is more one of American vs. international unitarian churches, because the name only indicates the traditional past of the movement rather than any break in doctrine.
'cause we don't really have much in the way of doctrine.