Even as world attention is riveted to the ongoing war between Israel and Gaza, not far to the east, another much greater catastrophe is taking place: the ethnic cleansing of Christians in Iraq. A community that has been under siege since the Arab-Islamic takeover of Persia, Mesopotamia and the Levant in 633-654, Christians in Iraq (mostly ethnic Assyrians) have held on for centuries, suffering a lot in the process, but still managing to survive. However, the now-notorious ISIS has proved to be the Christians' nemesis. On June 10, the ISIS took over Mosul, Iraq's second largest city located on the right bank of the Tigris river in the northern part of the country. On July 19, the ISIS declared to the Christians of Mosul through the loudspeakers of masjids: become Muslims or pay the Jiziya or leave the city. Needless to say, the Christians of Mosul fled en masse to the safety of Kurdish-controlled areas further north. The Kurds are Sunni Muslims too, but they don't share the hardline version of Islam that ISIS' Sunni Arabs espouse. Kurdish leaders have vowed to protect Christians from the ISIS, confident of the power of Peshmerga fighters. The city of Mosul, which has been a cultural capital of sorts for Iraqi Christians for centuries, now has ZERO Christians. It is the greatest of tragedies. A sad end to a glorious chapter in world history. Christianity in Mesopotamia, the modern Iraq of today, is as old as history itself. The references to the land, its cities, its kingdoms and its people, are countless in the Bible, both parts of it - the Old Testament and the New. The Tigris and Euphrates are two of four rivers mentioned in the Book of Genesis said to be arising within the Garden of Eden. Abraham, the Biblical patriarch revered by Jews, Christians and Muslims, belonged to the city of Ur on the Euphrates in southern Mesopotamia. According to the Bible, he migrated from Ur and settled in the land of Canaan, guided by God. The Mesopotamian empires of the Assyrians and Babylonians, are frequently mentioned in the Bible. The famed city of Babylon appears throughout the Hebrew Bible, including descriptions of the 'Babylonian Captivity', and also features prominently in several prophecies. The stories of a number of prophets in the Bible reveal how they warned the Hebrews of the consequences of worshipping the deities of Assyrians and Babylonians, instead of the Lord of the Hosts, YHWH. Often, convincing the Israelites became a test for the prophets themselves. There are the stories of Nahum, Jeremiah, Isaiah. But my favorite story is that of Jonah. Disobeying God, who had commanded him to teach to the residents on Nineveh in Assyria, Jonah is punished when a whale swallows him in the seas off Jaffa. When he repents, the whale regurgitates him and he finally goes to Nineveh to preach. In the 1st century AD, two of Jesus' Apostles, Thomas and Thaddeus (Jude) brought Christianity to Mesopotamia. The Assyrian people became Christian. Their main centre was Nineveh. When Nineveh declined, Mosul on the opposite bank of the Tigris became their capital, from where they have been driven today. During all this time, the Assyrians had been ruled by several peoples: Achamenid Persians, Greek Selucids, Iranian Parthians, Romans and finally Byzantines and Sassanids. But still they thrived. The Christians' real troubles started when the Muslim Arabs conquered the region after defeating the Byzantines and Sassanids. Arabs, Kurds and Turks, all of whom were Muslims, migrated to Mesopotamia. Assyrians became dhimmis in a Dar-ul-Islam. Still, they held on in northern Iraq. In the 1300s, Tamerlane (or Sultan Taimur as we call him in South Asia), carried a huge massacre of Assyrian Christains in northern Iraq. That is when their demographic decline began. Christians managed to survive the Ottoman period. By the time of British rule in the region in the 20th century, they had even begun to prosper. But then came Saddam Hussein and the Baath Party, during whose rule, while they were tolerated, their cultural, ethnic and religious identities were repressed. So much so that a high-ranking Saddam confidante like Tariq Aziz had to use an Arabic name instead of his real one (Mikhail Yuhana). Post-Saddam, it has been one tragedy after another for the Christians, culminating in their ouster from Mosul. While Christians still live in the Kurdish and southern, Shia-dominated areas of Iraq, their future is highly uncertain. Their story mirrors those of their counterparts in other Middle Eastern countries like Egypt, Syria, Lebanon and Jordan. They have lost or are losing the land of their forefathers, even as Christian and other nations watch helplessly. Their fate proves that change is the only constant in this world. Nothing else is the reality.