Dionysius IV nicknamed Muselimes (Greek Διονύσιος Δ΄ Μουσελίμης) was a Greek clergyman of the 17th century who served five terms as Patriarch of Constantinople.
Dionysius was born in Constantinople. He was elected Metropolitan of Larisa on August 9, 1662 while still a layman. In 1671, he became Patriarch of Constantinople for the first time. During his first term, Dionysius wrote his famous work "To the Calvinists concerning the dogma of the Orthodox Church" which outlined to the Reformed Church the position of Orthodoxy concerning their tenets of faith.
Over all, Dionysius served five terms as Patriarch:
During those years he came into conflict with James whom he dethroned twice from the Ecumenical throne: in 1682 and 1686. James, in turn, had Dionysius dethroned on October 17, 1687.
He was dethroned for the last time in 1694 and left for Moldavia where he died on September 23, 1696.
During his lifetime, Dionysius was jailed twice by the Turks: in 1679 and 1688. Both times he bribed himself out of his imprisonment.