The United States completed its withdrawal from Afghanistan late Monday, ending America’s longest war and closing a chapter in military history. Gen. Frank McKenzie, head of US Central Command, said a number of American citizens, likely numbering in “the very low hundreds,” were left behind, and that he believes they will still be able to leave the country.

The Taliban has not yet announced a new government after taking over Afghanistan. However, the insurgent group confirmed on Sunday that its supreme leader Hibatullah Akhundzada is in Kandahar. The inner workings and leadership of the Taliban have long been shrouded in secrecy but here is a rundown of what is known about their existing hierarchy.