#MazarMassacre: There is no way to precisely know how many were killed in weeks following the fall of Mazar to Taliban in 1998. Hazaras & Uzbeks were killed in reprisal for killing thousands of Taliban after a failed attempt by Taliban to take Mazar in May-July 1997. Source HRW.
Taliban tried to take Mazar twice before Aug1998. After Taliban killed Pres Najib in 1996, there was an attempt for peace. "I’ve proposed to Taliban not continue with this war since it’s better to solve our problems peacefully, through negotiations rather than fighting,” -Dostum.
For background from my thread on Pres Rabbani. Dostum ended up welcoming him to Mazar when Taliban took Kabul. A stronger alliance was made with Rabbani/Massoud. The fighting continued into 1997 and 1998.
Taliban killed civilians in Mazar. "I have been watching the television & the news on Kosovo & what's happening there but I think that from a humanitarian point of view, the situation in northwestern part of Afghanistan is much worse than what is going on over there.” - Abdullah
August 1998: The fall of Mazar to the Taliban was a turning point of the war in 90s. There are various reasons why Balkh province became Taliban territory. Below is from the Human Rights Report “MASSACRE IN MAZAR-I SHARIF” (hrw.org/legacy/reports…) detailing the abuse of Taliban. 
