To annex the Muzaffarid kingdom Timur would have to capture its two main cities: Isfahan and Shiraz.
Timur laid siege to the city and recaptured it with little effort.
After restoring his control over the city he ordered the massacre of the citizens who resisted; the death toll was between 70,000 – 200,000.
[4] After the massacre Isfahan remained loyal to Timur and so he went to capture Shiraz.
Unlike the events which occurred after the Siege of Herat Timur did not destroy any of the buildings and architecture allowing it retain its importance and influence in Persia.