Many books have been written about the Lost Tribes of Israel and their fate. Comprehensive material exists on numerous groups around the world that are in some way linked to the Jewish people. However, in the past, most of the works dealing with practical material were place in the category of folklore. Much of the material was based on hearsay evidence which could not be investigated or proved and was therefore not treated seriously by the scientific community. Although it is difficult to ascertain the veracity of the information today, the literature remains important, principally because of the opinions of the great Torah scholars in the matter. The aim of this book is to engage a new discussion on the subject of the Ten Tribes, corresponding in as far as possible to the current reality and without relation to past hearsay evidence. The book has two main objectives: firstly to present a general picture of to the reader of how the subject is reflected in the Bible, in the writings of our sages and in responsa of Torah luminaries through the generations; and secondly, to present the most recent information on the tribes and groups that possess many traditions apparently linking them to the Jewish people. It also relates the attitude of religious leaders today towards these various groups and to the work of the Amishav organization, and presents accounts of some of the expeditions of Amishav emissaries to the various groups. The report on these expeditions constitutes the practical side of the work. This book constitutes a sequel to "The Lost Tribes of Assyria," which described the activities of Amishav since its founding and presented a description of the different tribes and their relationship to the Jewish people. This volume contains both additional factual material and a discussion of the scholastic and philosophical aspects of the subject. It should be noted that the material presented here on each tribe, and also the theoretical material, was selected from a wealth of data collected by the Amishav organization. The book is titled "The Tribes of Israel," because it includes information not only on the Lost Ten Tribes, but also on various other groups which are related genealogically to the tribe of Judah, and which must be reintegrated in the Jewish people. I have totally dedicated myself to this enterprise since 1960. Amishav the organization on Behalf of the Dispersed of Israel, was founded in 1975 with the encouragement of Rabbi Zevi Yehuda Kook, of blessed memory, the head of the "Merkaz Harav" Yeshiva in Jerusalem and the spiritual leader of the Reglious Zionist Judaism. Rabbi Kook supported Amishav and encouraged its various activities to his last days. The objectives of the Amishav organization have remained constant since its inception, being both the scientific research of the Lost Tribes of Israel and the actual ingathering of these lost people, first back to Judaism and then to the Jewish people and the Land of Israel. All proceeds from sales of this book will go directly to the Amishav non-profit organization and its continued work.