Answer :

The Byzantine Empire lost a lot of its area after 1081due to the expansion of Islam. Also their lands were flooded by the Turkish settlers.

Hope this helps :)
mnadat9

Hello,

Question-after 1081 ,what was the byzantine being weakened by?

Answer- The Byzantine Empire held the capital Constantinople which was the center of trade at hat time. So everyone wanted it including the Ottamans. Due to the fast spreading islam the turkish army the Ottamans were able to conqure the capital and this caused the Byzantine Empire to collapse.