Page "Isaac II Angelos" Paragraph 6

The oppressiveness of his taxes, increased to pay his armies and finance his marriage, resulted in a Bulgarian uprising late in 1185.

The rebellion led to the establishment of the Second Bulgarian Empire under the Asen dynasty.

In 1187, Alexios Branas, the victor over the Normans, was sent against the Bulgarians but turned his arms against his master, and attempted to seize Constantinople, only to be defeated and slain by Isaac's brother-in-law Conrad of Montferrat.

Also in 1187, an agreement was made with Venice, in which the Venetian Republic would provide 40 – 100 galleys at six months ' notice in exchange for favorable trading concessions.

As each Venetian galley was manned by 140 oarsmen, that means there were about 18, 000 Venetians still in the Empire even after Manuel I's arrests.