The book, Sidra, written in the ancient language of Aramaic and dating to the 14th and 15th century, will soon be returned to Qaraqosh, one of the places the pope hopes to visit when he makes his historic trip to Iraq next month.

Jihadists swept through Qaraqosh and the rest of the Nineveh Plain east of Mosul in 2014 -- and stayed until October 2016.

They forced around 120,000 of Iraq's Christians to flee their homes, the biggest disaster to hit the minority community in its nearly 2,000-year history.

The manuscript was one of the oldest books in the Church of the Immaculate Conception, and was saved by local priests. It contains liturgical prayers for Easter services.

Ivana Borsotto, the head of FOCSIV, a federation of Christian organisations, gave the book to the pope "so that it may return home, to the church in that martyred land, in a sign of peace and brotherhood".