The Assyrian Genocide and Armenian Genocide of World War I conducted by invading Turks drastically reduced the Christian population of Iran, as they did with Turkey, Iraq and to a lesser degree north east Syria.
Though Iran recognizes Assyrian and Armenian Christians as ethnic and religious minorities (along with Jews and Zoroastrians) and they have representatives in the Parliament, they are nonetheless forced to adhere to Iran's strict interpretation of Islamic law. After the 1979 Revolution, Muslim converts to Christianity (typically to Protestant Christianity) have been arrested and sometimes executed. Youcef Nadarkhani is an Iranian Christian pastor who was arrested on charges of apostasy in October 2009 and was subsequently sentenced to death. In June 2011 the Iranian Supreme Court overruled his death sentence on condition that he recant, which he refused to do. In a reversal on 8 September 2012 he was acquitted of the charges of apostasy and extortion, and sentenced to time served for the charge of "propaganda against the regime," and immediately released.
The Christian presence in Yemen dates back to the fourth century AD when a number of Himyarites embrace Christianity due to the efforts of Theophilos the Indian. Currently, there are no official statistics on their numbers, but they are estimated to be between 3,000 and 25,000 people, and most of them are either refugees or temporary residents. Freedom of worship, conversion from Islam and establishing facilities dedicated for worship are not recognized as rights in the country's Constitution and laws. At the same time, Wahabbi activities linked to Al-Islah was being facilitated, financed and encouraged from multiple fronts including the Ministry of Endowments and Guidance, which says that its tasks "to contribute to the development of Islamic awareness and circulation of the publication Education and Islamic morals and consolidation in the life of public and private citizens."
The Missionaries of Charity founded by Mother Teresa has worked in Aden since 1992, and it has three other centers in Sana'a, Taiz and Hodeidah. Three Catholic nuns were killed in Hodeidah in 1998, two of them were from India and the third was from the Philippines at the hands of a member of Al-Islah named Abdullah al-Nashiri, who argued that they were calling Muslims to convert to Christianity. In 2002, three Americans were killed in Baptists Hospital at the hands of another Al-Islah member named Abed Abdul Razak Kamel. Survivors say that the suspect (Al-Islah) was "a political football" who had been raised by Islamists, who talked about it often in mosques and who described hospital workers as "spies." But they emphasized that these views are only held by a minority of Yemenis. In December 2015, an old Catholic church in Aden was destroyed.
Since the escalation of the Yemeni crisis in March 2015, six priests from John Bosco remained, and Twenty workers for charitable missions in the country, described by Pope Francis by the courage to fortitude amid war and conflict. He called the Apostolic Vicar of Southern Arabia to pray for all the oppressed and tortured, expelled from their homes, and killed unjustly. In all cases, regardless of the values and ethics of the warring forces in Yemen on religious freedom, it is proved that the Missionaries of Charity were not active in the field of evangelization according to the testimonies of beneficiaries of its services.
On 4 March 2016, an incident named Mother Teresa's Massacre in Aden occurred, 16 were killed including 4 Indian Catholic nuns, 2 from Rwanda, and the rest were from India and Kenya, along with a YemenI, 2 Guards, a cook, 5 Ethiopian women, and all of them were volunteers. One Indian priest named Tom Ozhonaniel was kidnapped. The identities of the attackers are unknown, and media outlets published a statement attributed to Ansar al-Sharia, one of the many jihadist organizations currently active in the country, but the group denies it's involvement in the incident.