Patriarch Gregory II Youssef, also known as Gregory II Hanna Youssef-Sayour (October 17, 1823 – July 13, 1897), was Patriarch of the Melkite Greek Catholic Church from 1864 to 1897. Gregory expanded and modernized the church and its institutions and participated in the First Vatican Council, where he championed the rights of the Eastern Catholic Churches. Gregory is remembered as a particularly dynamic patriarch of the Melkite Church. He is recognized as one of the forerunners of interconfessional dialogue and as an advocate for preserving the traditions and autonomy of the Melkites.