Iraq has officially approved a law that makes December 25, Christmas Day, a national holiday in the country.

To make the passing of the law public, the government has also posted about it on Twitter, greeting the Christian citizens and all Iraqis around the world a "Happy Christmas."

The Iraqi government passed the law exactly on Dec. 25, "on the occasion of the birth of Jesus Christ," it said in a statement first reported by CNN. The Cabinet agreed to amend the country's law on national holidays, making Christmas Day a holiday not just for Christian communities but all parts of the country as well.

The decision has been considered a major step in the advancement of religious diversity in the country after it suffered invasions by the ISIS that were believed to be targeted on Christians and other religions that were considered minorities.

There were about 1.4 million Christians in the country before the US-led invasion of Iraq in 2003 opened it vulnerable to violent groups such as ISIS.

A 2016 documentary from CNN had even estimated that at one point, there were nearly 5 million Assyrian Christians in Iraq. Through decades, however, many of them have migrated to the United States, Europe, and Australia.

The year 2014 saw the peak of ISIS invasions and more Christians were displaced that year. Before the ISIS invasions hit records high, there were only 300,000 Christians who stayed In Iraq. Also, at the time, many believed that Christianity has met its demise in the country.

ISIS-controlled Mosul, Iraq's second-largest city, in 2014. In Bartella, ISIS was said to have marked Christian houses with the Arabic equivalent of the letter "N" that stands for "Nazarene." During the most peaceful times prior to ISIS rising, people in Bartella were mostly Christians and people spoke in Syriac, a dialect which ancient language experts said was spoken by Jesus, according to the CNN documentary.

The ISIS pushed Christians and other minority groups away from Mosul. CNN estimated that there were only about 20 or 30 Christians who remained in the city.

The ISIS had also conducted the same invasions in Nineveh where as many as 100,000 Christians were displaced. The group had also destroyed ancient Christian monastery and other emblems, seemingly wanting to bury the 2,000-year Christian civilization. Iraqis believed that the group wanted "genocide."

The group, however, remains to be violent even after progress was made in most recent years. On Wednesday, Dec. 26, reports emerged that ISIS claimed responsibility for a car bomb incident in Tal Afar, about 80 kilometers west of Mosul. The blast killed two people and wounded 11 others more.