The Samaritans are not a Christian group nor would the Jews consider them to be Jews.  There is a school of thought, however, that they preserve a pre-rabbinical form of Jewish worship.  They do practice animal sacrifice to this day.  The Samaritans have preserved a version of the Torah that you will occasionally see referenced in the footnotes of Bibles as the Samaritan Pentateuch. It is a text type that deviates from the Masoritic text in some 2000 places. Often it agrees with the Septuagint, sometime there are clear differences as in the centrality of Mt. Gerizim, the samaritan place of worship (recall the story of the Samaritan women in John 4). There are also texts that agree with it among the Dead Sea Scrolls. 

The Samaritans today say that they have a Torah scroll that was written by Aaron himself. In general the Samaritans accept only the 5 books of Moses as inspired, some say that their canon also contains the book of Joshua but most say that the Samaritans consider their version of Joshua as secular history. If Joshua is included their canon is called by many the Hexateuch.

There is some dispute over just who the Samaritans are and how they came to be. The Samaritans believe that the Jews parted company with them in the 11 th century B. C. around the time of Eli. We recall the story in I Samuel 2 where the Lord rejects Eli and his Family. The Biblical naritive continues with Samuel becoming the prophet of the Lord continuing the line of faith through Samuel's ministry. 

In my youth I learned that they have their origin in an interesting story in II Kings 17. It seems that when the northern kingdom of Israel fell and the people were deported to Assyria, the Assyrians resettled a mixture of peoples in the land.

24 The king of Assyria brought people from Babylon, Cuthah, Avva, Hamath and Sepharvaim and settled them in the towns of Samaria to replace the Israelites. They took over Samaria and lived in its towns. 25 When they first lived there, they did not worship the LORD; so he sent lions among them and they killed some of the people. 26 It was reported to the king of Assyria: "The people you deported and resettled in the towns of Samaria do not know what the god of that country requires. He has sent lions among them, which are killing them off, because the people do not know what he requires."

 

27 Then the king of Assyria gave this order: "Have one of the priests you took captive from Samaria go back to live there and teach the people what the god of the land requires." 28 So one of the priests who had been exiled from Samaria came to live in Bethel and taught them how to worship the LORD.

 

29 Nevertheless, each national group made its own gods in the several towns where they settled, and set them up in the shrines the people of Samaria had made at the high places. 30 The men from Babylon made Succoth Benoth, the men from Cuthah made Nergal, and the men from Hamath made Ashima; 31 the Avvites made Nibhaz and Tartak, and the Sepharvites burned their children in the fire as sacrifices to Adrammelech and Anammelech, the gods of Sepharvaim. 32 They worshiped the LORD, but they also appointed all sorts of their own people to officiate for them as priests in the shrines at the high places. 33 They worshiped the LORD, but they also served their own gods in accordance with the customs of the nations from which they had been brought.

 

34 To this day they persist in their former practices. They neither worship the LORD nor adhere to the decrees and ordinances, the laws and commands that the LORD gave the descendants of Jacob, whom he named Israel. 35 When the LORD made a covenant with the Israelites, he commanded them: "Do not worship any other gods or bow down to them, serve them or sacrifice to them. 36 But the LORD, who brought you up out of Egypt with mighty power and outstretched arm, is the one you must worship. To him you shall bow down and to him offer sacrifices. 37 You must always be careful to keep the decrees and ordinances, the laws and commands he wrote for you. Do not worship other gods. 38 Do not forget the covenant I have made with you, and do not worship other gods. 39 Rather, worship the LORD your God; it is he who will deliver you from the hand of all your enemies." (II Kings 17.24-39)

The main reason for the exile was idolatry.  The priest that would have been brought back would likely have the same sorts of pagan influences as the Israelites did.  It seems unlikely that this group would have preserved much of a 'pure' tradition.

The more generally accepted notion is that the Samaritans grew out of the part of the returning exiles that were driven off by Nehemiah while he was rebuilding Jerusalem and the temple.

 23 Moreover, in those days I saw men of Judah who had married women from Ashdod, Ammon and Moab. 24 Half of their children spoke the language of Ashdod or the language of one of the other peoples, and did not know how to speak the language of Judah. 25 I rebuked them and called curses down on them. I beat some of the men and pulled out their hair. I made them take an oath in God's name and said: "You are not to give your daughters in marriage to their sons, nor are you to take their daughters in marriage for your sons or for yourselves. 26 Was it not because of marriages like these that Solomon king of Israel sinned? Among the many nations there was no king like him. He was loved by his God, and God made him king over all Israel, but even he was led into sin by foreign women. 27 Must we hear now that you too are doing all this terrible wickedness and are being unfaithful to our God by marrying foreign women?" 

 

 28 One of the sons of Joiada son of Eliashib the high priest was son-in-law to Sanballat the Horonite. And I drove him away from me. (Nehemiah 13.23-28)

This group does seem more likely to have preserved something like the traditions of their fathers although they had intermarried with people from other nations.  There is a likelihood that the present day Samaritans are a mix of both groups as they seemingly did not value remaining ethnically pure.

Still the Samaritan Pentateuch is another witness to the Torah and is in general agreement with the traditional text of the Jews.

The Samaritan scriptures contain the following:

The Samaritan Pentateuch:

  1. Genesis
  2. Exodus
  3. Leviticus
  4. Numbers
  5. Deuteronomy

Joshua - probably a secular history