At the same time, al-Muwaffaq also had to contend with the ambitions of Ahmad ibn Tulun in the western provinces.
Ibn Tulun and the Abbasid regent fell out in 875/6, on the occasion of a large remittance of revenue from Egypt to the central government.
Counting on the rivalry between the Caliph and his over-mighty brother to maintain his own position, Ibn Tulun forwarded a larger share of the taxes to al-Mu'tamid instead of al-Muwaffaq: 2.2 million gold dinars went to the Caliph and only 1.2 million dinars to his brother.
Al-Muwaffaq, who in his fight against the Zanj considered himself entitled to the major share of the provincial revenues, was angered by this, and by the implied machinations between Ibn Tulun and his brother.
Al-Muwaffaq nominated Musa ibn Bugha as governor of Egypt and sent him with troops to Syria, but a lack of funds led to the expedition's failure before even reaching Egypt.
In a public gesture of support for al-Mu'tamid and opposition to al-Muwaffaq, Ibn Tulun assumed the title of "Servant of the Commander of the Faithful" (mawlā amīr al-muʾminīn) in 878.
With the support of al-Mu'tamid, in 877/8 Ibn Tulun managed to be assigned responsibility for the entirety of Syria and the Cilician frontier zone (Thughur) with the Byzantine Empire.

In 881, Ibn Tulun added his own name to coins issued by the mints under his control, along with those of the Caliph and heir apparent, al-Mufawwad.
In the autumn of 882, the Tulunid general Lu'lu' defected to the Abbasids, and the cities of the Thughur rejected Tulunid rule, forcing Ibn Tulun to go once again in person to Syria.
Al-Mu'tamid used the moment to escape from his confinement in Samarra, and with a small entourage made for Tulunid domains.
Messengers from the Caliph reached Ibn Tulun at Damascus, and the ruler of Egypt halted and awaited the Caliph's arrival with great anticipation: not only would the sole source of political legitimacy in the Muslim world reside under his control, but he would also be able to pose as the "rescuer" of the Caliph from his overreaching brother.
In the event, however, Sa'id ibn Makhlad managed to alert the governor of Mosul, Ishaq ibn Kundaj, who overtook and defeated al-Mu'tamid and his escort at al-Haditha on the Euphrates.
Al-Mu'tamid was brought back to Samarra (February 883), where he was placed under virtual house arrest in the Jawsak Palace.
In May/June, he was even moved south to Wasit, where al-Muwaffaq could keep an eye on him in person.
Only in March 884 was the powerless Caliph allowed to return to Samarra.
In the meantime, he was obliged to denounce Ibn Tulun, and appoint—nominally at least—Ishaq ibn Kundaj as governor of Syria and Egypt.

In 886/7, the Caliph conferred the title of "king" on the long-time ruler of Armenia, Ashot I (r. 862–890).
Although the Armenian king continued to pay tribute to the Abbasid court and recognize its suzerainty, both he and the various minor Armenian princes were de facto independent monarchs.
At the same time, al-Muwaffaq also had to contend with the ambitions of Ahmad ibn Tulun in the western provinces. Ibn Tulun and the Abbasid regent fell out in 875/6, on the occasion of a large remittance of revenue from Egypt to the central government. Counting on the rivalry between the Caliph and his over-mighty brother to maintain his own position, Ibn Tulun forwarded a larger share of the taxes to al-Mu'tamid instead of al-Muwaffaq: 2.2 million gold dinars went to the Caliph and only 1.2 million dinars to his brother. Al-Muwaffaq, who in his fight against the Zanj considered himself entitled to the major share of the provincial revenues, was angered by this, and by the implied machinations between Ibn Tulun and his brother. Al-Muwaffaq nominated Musa ibn Bugha as governor of Egypt and sent him with troops to Syria, but a lack of funds led to the expedition's failure before even reaching Egypt. In a public gesture of support for al-Mu'tamid and opposition to al-Muwaffaq, Ibn Tulun assumed the title of "Servant of the Commander of the Faithful" (mawlā amīr al-muʾminīn) in 878. With the support of al-Mu'tamid, in 877/8 Ibn Tulun managed to be assigned responsibility for the entirety of Syria and the Cilician frontier zone (Thughur) with the Byzantine Empire.
In 881, Ibn Tulun added his own name to coins issued by the mints under his control, along with those of the Caliph and heir apparent, al-Mufawwad. In the autumn of 882, the Tulunid general Lu'lu' defected to the Abbasids, and the cities of the Thughur rejected Tulunid rule, forcing Ibn Tulun to go once again in person to Syria. Al-Mu'tamid used the moment to escape from his confinement in Samarra, and with a small entourage made for Tulunid domains. Messengers from the Caliph reached Ibn Tulun at Damascus, and the ruler of Egypt halted and awaited the Caliph's arrival with great anticipation: not only would the sole source of political legitimacy in the Muslim world reside under his control, but he would also be able to pose as the "rescuer" of the Caliph from his overreaching brother. In the event, however, Sa'id ibn Makhlad managed to alert the governor of Mosul, Ishaq ibn Kundaj, who overtook and defeated al-Mu'tamid and his escort at al-Haditha on the Euphrates. Al-Mu'tamid was brought back to Samarra (February 883), where he was placed under virtual house arrest in the Jawsak Palace. In May/June, he was even moved south to Wasit, where al-Muwaffaq could keep an eye on him in person. Only in March 884 was the powerless Caliph allowed to return to Samarra. In the meantime, he was obliged to denounce Ibn Tulun, and appoint—nominally at least—Ishaq ibn Kundaj as governor of Syria and Egypt.
In 886/7, the Caliph conferred the title of "king" on the long-time ruler of Armenia, Ashot I (r. 862–890). Although the Armenian king continued to pay tribute to the Abbasid court and recognize its suzerainty, both he and the various minor Armenian princes were de facto independent monarchs.
Al-Mu'tamid