What caused Judaism to break into branches? Are the branches even seen as a division? Does theology differ among them?
THE RELIGION GUY’S ANSWER:
The questioner has “a Christian background" and, thus, is familiar with a religion made up of separate groups.
Christianity has long been divided into four main families, the so-called “Oriental Orthodox,” the Eastern Orthodox, Catholicism and Protestantism. A fifth family of new, independent churches in the developing world developed in the 20th Century.
Islam, too, suffered the big breach between Sunni and Shia believers in the first century that continues to be troublesome, and sometimes lethal, today.
By contrast, for much of its history Judaism was essentially one united faith, though naturally it encompassed various movements, tendencies, cultures and local variations.
That began to change with the modern emancipation and assimilation of Jews in Western Europe. A liberal form of the faith developed, especially in Germany, and flourished among 19th Century German immigrants in the United States. Worship was simplified, Hebrew was downplayed in favor of worship in common languages with Protestant-style sermons, and age-old observances were eliminated or made matters of personal choice.
The resulting liberal branch or denomination eventually known as Reform Judaism centered on three North American institutions, the Union of American Hebrew Congregations (now Union for Reform Judaism) that 34 synagogues formed in 1873, Hebrew Union College to train rabbis (1875), and the Central Conference of American Rabbis (1890).