What are the main branches of Islam practiced in Azerbaijan?

Azerbaijan is a predominantly Muslim country, with the population primarily divided between two main branches of the faith:

• Shiʿi: More than three-fifths of the population identify as Shiʿi Muslims. This affiliation developed significantly under Persian cultural and social influence beginning in the 16th century.123
• Sunni: Approximately one-third of the population identifies as Sunni Muslim.12

While these two branches represent the vast majority of the religious landscape, a very small percentage of the population belongs to other faiths, including the Russian Orthodox and Armenian Orthodox churches.2