The Mandaeans (Subbiyun) have survived in the marshy area of the lower plains of Babylonia and have lived and continue to live basically in around Shat al-Arab and along the rivers that converge on it, Tigris and Euphrates, and the Karun, in the Iranian Khuzistan. The Mandaeans had settled for centuries in these distinct areas and generally lived in straw and mud huts. Today, there is in addition a significant Mandaean community in Baghdad. With continuous persecution, the population of the Mandaeans in Diaspora has increased significantly. They make proficient goldsmiths, blacksmiths, carpenters (boat builders), shepherds and farmers.

The Mandaeans have always had a special interest in the study of astronomy and mathematics just like their forefathers, the ancient Babylonians. The dean of translators in this aspect was Thabit bin Qurrah (ca. 836-901), who had a patron in the successor of al-Mutawakkil. He is credited with having translated into Arabic-in collaboration with his son and other disciples-the bulk of the Greek mathematical and astronomical works including those of Archimedes (d. 212 BC). Other known Mandaeans are Ibrahim bin Sinan, who was a famous engineer during the Abbasid period and Albutani, who was a mathematician and astronomer. Two of their best-known figures in modern Iraqi history have been Dr. Aabdul Jabar Abdullah, a well-known physicist and Malik Saif, aka Comrade Kamal, a distinctive member of the Central Committee of the Iraqi Communist Party during the middle of the 20th century.

Mandeaen priest baptizing in the name of John the Baptist The Mandaeans are sometimes referred to as Sabaeans, but one must not confuse them with the Sabaeans of the early Yemen history, in the southwestern edge of the Arabian Peninsula. Mandaeans during Islam acquired a dhimmi status just like the Christians and the Jews, and were classified by Moslems as a "protected" sect. Traditionally though when a Mandaean family converts to any other religion, although not abandoning its ethnic identity, it no longer is considered Mandaean.
For the Mandaeans, Sunday is considered a holy day, which they call hab?aba (habshaba). The ceremony practiced on Sunday could last almost all morning. Mandaeans or "Saint John Christians", as they are called sometimes, believe in God and His Monotheism. God is called in their holy book and other religious sources, "The Great Life or The Eternal Life". Also, they believe that Adam was their first prophet and teacher. Their second prophet was Sheet who is named "Shetel" in Mandaiac; followed by Sam son of Noah. Aspects of the Mandaean Religion include: Monotheism; Baptism; Praying; Fasting and Giving (moral and material).

The religious ideas of the Mandaeans show some remarkable similarities to the ancient doctrines, whether pagan or Christian. In the Ginza "Treasury", perhaps the best known of the Mandaic sacred books, we find at least seven different accounts of the origins of the cosmos, each with features most difficult to reconcile. The Mandaeans hold on the immense shoulders of Ur, an enormous serpent-like sea monster of the abyss. Most of the stories about the language and religion of the Mandaeans were collected by Catholic missionaries, who acknowledged that great uncertainties surrounded them. First, the name; it is not certain what Mandaean means but it is thought that it came from their own claim of being Mandaiia, which is related to madda, meaning "knowledge". The most sacred Mandaean ceremonies are performed by the priests, who are called tarmidia "disciple," inside a fenced-off area called a mandi with a building inside this area called manda or bimanda (from bet manda, "house of knowledge". Second, it is thought that the name came from Manda d-Hiia, meaning "Knowledge of Life". What is certain is the name their Arab neighbors gave them: Subba, "baptizers," "those who immerse [themselves in water]. Baptism and submersion in the flowing water of a river is the principle religious practice. For Mandaeans, flowing water is considered life-creating force of the world.

A very interesting religious ritual is giving the new born four names; one used during religious rituals given by the priest, second is the family name, a third is a sort of clan name, and a personal Arab name used for everyday life that does not has any astrological value (not to cause particular problems). The astrological name, called the "name of the sign of the zodiac" is calculated in this manner: the (12) signs of the zodiac, from Aries to Pisces, are placed in a circle, and beginning from the sign corresponding to the month of the child's birth, the priest passes from sign to sign, for as many positions as there were hours in the day until the moment of birth, to arrive at the sign of the zodiac under whose influence lay the hour of the day in which the birth occurred. The numerical value of this sign is what counts, and the numerical value of the astrological name of the child's mother is subtracted from this. Once a certain number has been arrived at, a list of names corresponding to that number is compiled from the list in the "Book of the Zodiacs," and the parents choose a name from that list. There are other rituals that evolve around constant consultation of the stars and others in which the priests redact horoscopes and predict the future. Other rituals include the daily ablution of all parts of the body, and others, which I will not get into in this short article.
Within the community of believers, who are known as the laupa, there are those who are not priests but know how to read and write classical Mandaean language and are called ialupia "cultured secular layman". They have access to the sacred texts and the knowledge those texts convey. Above the priests are the ganzibria (singular ganzibra) meaning "bishop", a name connected to ginza "treasury," which could mean also "the treasurer of knowledge." Heading the religious hierarchy was a ri? (rish) ama "head of the people" but this position has not been filled since the 19th century, which few many describe as a sign for a declining of Mandaeanism.
The classical Mandaean language is a type of Oriental Aramaic, with features similar to those of the language of the Babylonian Talmud and with external influence, especially Persian. Spoken Mandaean, called raTtna, uses a simplified language system and betrays considerable Arabic influence. The alphabet is made of (24) signs, of which (22) represent the normal letters, the 23rd is a double letter, and the last one is the repetition of the first "a". In this way a multiple of (6) is obtained (the number that symbolically indicates Mandaean things), as well as the correspondence to the number of hours in a day. Unlike other Semitic languages, the vowels do not appear as little dots or secondary graphical signs compared to consonants but are always written in their full form, being thought of as letters like the rest.

The oldest Mandaean liturgical text is a set of collection of Hymns of Praise called Qulasta. Other parts of the text are Sidra d-Ni?mata "The Book of Souls", containing liturgies for the maSsbuta (plural maSsbutiata) "solemn baptism"; prayers for the masiqta "elevation, a ceremony to help the soul"; Asut Malkia "The Greeting to the King"; Rahmia (everyday prayers); Abahatan Qadmaiia "Our First Fathers"; prayers for weddings; drap?a "ceremonial standard with a support in the form of a cross"; zidqa brika "blessed offerings"; klila "crown of myrtle", and so forth. Other texts include Sidra Rba "Great Book" or Ginza "Treasurer" iamina (of the right) and smala (of the left). In addition, in Mandaic a large number of magic texts have been redacted.
Around 1290, a learned Dominican Catholic from Tuscany, Ricoldo da Montecroce, or Ricoldo Pennini, was in Mesopotamia where he met the Mandaeans. He described them as follows:
"A very strange and singular people, in terms of their rituals, lives in the desert near Baghdad; they are called Sabaeans. Many of them came to me and begged me insistently to go and visit them. They are a very simple people and they claim to possess a secret law of God, which they preserve in beautiful books. Their writing is a sort of middle way between Syriac and Arabic. They detest Abraham because of circumcision and they venerate John the Baptist above all. They live only near a few rivers in the desert. They wash day and night so as not to be condemned by God, ..."
Catholic missionaries have other encounters with the Mandaeans towards the middle of the 16th century. But the Mandaeans remained, or were kept, unknown, and Pennini's information and few others remained unpublished until 1940s. What was the reason behind this neglect by the Vatican?
Pope Eugene IV (March 3, 1431-February 23, 1447) signed agreements, on the basis of orthodoxy, with certain hitherto dissident Nestorian groups in Mesopotamia in 1444 and in Cyprus in 1445. The Nestorians of Cyprus consequently converted to Catholicism as a whole and their bishop asked that they be called Chaldeans from that time on. In 1552, a Nestorian monk, Sulaqa, traveled to Rome, accepted Catholicism and was proclaimed patriarch over the Assyrians in 1553. But the title was eventually replaced with the title patriarch over the Chaldeans to be in parallel with the title Chaldean given to the Nestorian converts in Cyprus.

The Catholic missionaries have been contacting the Christians of northern Mesopotamia yet earlier but this is not the topic of the article. And at the same time the contacts of the Catholics continued with the Mandaeans. Some Portuguese Jesuits had met some "Saint John Christians" or Mandaeans around the Strait of Hormuz in 1559, when the Portuguese fleet met the Ottoman Turkish army in Bahrain and forced the latter to retreat but lost later in 1581. Communications between the Catholic missionaries and these Mandaean Christians continued, as the latter seemed to be willing to obey the holy Roman Church. They already knew and used the seven Catholic sacraments and the related ceremonies in their lives.
In 1604, Gerolamo Vecchietti, a Tuscan and one of the finest of narrators, who was entrusted by the Pope and other European sovereign to look for manuscripts in Oriental languages, was traveling along the Baghdad-Basrah route. He stopped by a small village where he found a group of Mandaean Christians. One of these had fled from Kuzistan, spoke Portuguese and he provided information to Vecchietti about his people, in all he said that they were around 60,000 of them. About the Mandaeans' language, Vecchietti concluded that the Mandaeans called it Chaldean language, although he identified it as Syriac. After arriving in Basrah, Vecchietti met many Mandaeans. Having gathered what he could from the Mandaeans in term of news and information, Vecchietti deduced that the Mandaeans were "a generation of the ancient Chaldean Christians," reduced to ignorance by Islamic persecution, stated Professor Lupieri. We know that many of the Christians of southern Mesopotamia were forced into Islam after the latter's conquest of southern Mesopotamia during the second quarter of the 7th century. This was due to many reasons, most importantly perhaps was to escape the heavy taxes levied on non-Moslems. Although we see prominent Christians in the fields of medicine, science and in the courts of the Abbasid Caliphates, the Christians in general were decreasing rapidly in numbers in southern Mesopotamia, unlike northern Mesopotamia, and just before the fall of the Abbasid Dynasty and Baghdad in 1258 at the hands of the Mongols, the Christians in southern Mesopotamia were a small minority.

Everything in the Mandaeans' history indicates a strong descendent link to the ancient Babylonian society of southern Mesopotamia, which included the ancient Chaldeans in its fabric. One must wonder who is more authentic to claim a descent from the ancient Babylonians and the Chaldeans? The Mandaeans who continue to live in southern Mesopotamia and have many religious, language, ritual, and other aspects of those original forefathers or some Christians living in Assyria, over 300 miles to the north, whom the Vatican wrongly called Chaldeans? The Vatican had made its decision to call every Church of the East member "wrongly labeled Nestorian" convert to Catholicism as a Chaldean for consistency with what had happened in Cyprus in 1445. But it had to figure out a way to deal with these new peoples the Roman Catholics have encountered, i.e. the Mandaeans. Therefore, the Vatican decided to keep the Mandaeans, the heirs of ancient Babylonians, somehow in the shadows. The Vatican figured, what better name to propagate than that of some people mentioned in the Bible, the ancient Babylonians and ancient Chaldeans, who have shown signs of survival in southern Mesopotamia through the Mandaeans and their ways!

What did the Vatican cause by doing so? From one side, the Vatican denied the small community of the Mandaeans their legitimate descent from the ancient Chaldeans. This was true since the term Chaldean was wrongly generalized to include every Nestorian convert to Catholicism from Cyprus to India, even though these people have no connection with the ancient Chaldeans. And from the other side, the Vatican put the foundation to destroy its real rival church by creating a new ethnic group out from the Church of the East, i.e. the Chaldeans.
Hence, the two most unfortunate victims of this unforgiving move by the Vatican, in my opinion, were: the Mandaeans and the Assyrians.

From The Assyrian Society of UK
http://www.atour.org/news15_2.htm