[1]: 225–227 Amcazade Koprulu Huseyin Pasha was close to ordinary Ottoman Muslim subjects being a member of the Mevlevi Order.
He participated at the campaign for Siege of Vienna in 1683, as a high staff officer in the Ottoman army commanded by the Grand Vizier Merzifonlu Kara Mustafa Pasha, who was his close relative.
On 1694 he was appointed the Kapudan Pasha (Ottoman admiral-in-chief) and was instrumental -with the help of Mezzo Morto Huseyin Pasha- in retaking of Chios from the Venetians in 1695.
In a War Council planning on what to do next, Amcazade Huseyin Pasha proposed that the Ottoman army should go and put the fortress of Varaždin under siege.
It was hoped that during the negotiations for peace to take place at Karlowitz, he could use family ability to get best possible terms for the ending of the long war against the Holy League of 1684, a coalition of European powers including the Habsburg monarchy, the Polish–Lithuanian Commonwealth, the Republic of Venice and Peter I of Russia.
New cultivators, from nomadic Turcomans, were induced to settle in places like Urfa, Malatya, Antalya and Cyprus where the numbers of agricultural peasants had decreased to very low levels.
Efforts were made to develop a new manufacturing base, in place of devastated Ottoman craft industries and replacing imports from Europe.
The lower rank galleon men were properly and regularly housed in barracks; paid well and even their retirement was thought of for the first time in Ottoman navy.
Giving Amcazade Huseyin a free hand in governing his realm, he retreated to a court life, not in Istanbul but in the old palace in Edirne.
As soon as the effects of Treaty of Karlowitz were over, Feyzullah Efendi collected around him a clique of relatives and allies; started appointing them to key state posts and became the centre of intrigues against the Grand Vizier Amcazade Huseyin.
From then onwards whenever the state under Amcazade Huseyin started affecting adversely his interests, Feyzullah Efendi was able to intervene and stop the application of such a policy.
One of the oldest wooden coastal mansions on the Bosphorous near the first suspension bridge, is the partial remains of a Yalı belonging to him is called the "Koprulu Amcazade Huseyin Yalisi".