No single body has been in a leadership position over the entire Jewish diaspora since CE 70 when the Second Temple was destroyed in the First Jewish-Roman War.
Individual religious congregations or synagogues may identify with one of several branches of Judaism and may belong to an organization associated with that branch, but these organizations usually have very limited power over the individual synagogues. There can be differences in the positions and practices of synagogues identifying with the same branch of Judaism.
Since the lines of demarcation between branches of Judaism are far from clear and vary by both location and date, synagogues in all branches of Judaism are collected in the subcategories of this stream and organized by geography. As the total number of synagogue categories on WikiTree is presently small, the only current geographic divisions are by country.
If a given synagogue's affiliation with an organization of a specific branch of Judaism (such as United Synagogue of Conservative Judaism, Union for Reformed Judaism or Orthodox Union, etc.) is known, the category for the synagogue may also be made a subcategory of that organization or one of its subcategories.
This category is managed by the Jewish Roots Project in association with the Categorization Project. For assistance with this or related categories ask in G2G making sure to tag your question with both categorization and Jewish Roots.