What is an Islamic Emirate?

The Taliban ruled for five years in Afghanistan from 1996 to 2001, establishing an Islamic emirate system. What is an Islamic emirate and what transpired during the Taliban’s five-year emirate in Afghanistan?
The Taliban’s Islamic emirate came to power in 1996 while the country was embroiled in a civil war that followed the fall of the Soviet-backed president, Dr. Najibullah, in the early 1990s. The Taliban’s emirate was originally established in Kandahar, under the leadership of Mullah Omar, the Taliban’s founding leader. After their establishment in Kandahar, the group rapidly captured wider territories in Afghanistan and soon established their emirate in Kabul, which held power for five years until being toppled by the US and its Afghan allies.