This work treats of both the general law and the customary law of succession in southern Nigeria, with special reference to the newly established Mid-Western Region. The rules of the various systems of the customary law of succession of the peoples inhabiting our area of special reference - the Mid-Western Region - have been examined in defined patterns; although the opportunity has also been taken to point out instances of local variations occurring within the patterns, as well as those of similarities existing between systems dealt with in different patterns. The work is in five parts. Part One gives an outline of the legal system of the Mid-Western Region, including a brief sketch of certain topics - the creation of the Region, its position, extent and peoples - serving, as it were, as a background for an intelligent understanding of the legal system. Part Two deals with the general law. Chapter Two contains a brief account of the law relating to the administration of estates; while Chapters Three and Four examine the effect of a Christian or monogamous marriage on intestate succession. Part Three is concerned with the process of the administration of estates under customary law in southern Nigeria generally. Chapter Five gives an account of the performance of the burial and funeral ceremony of the deceased, and the connexion between the performance of this ceremony and the succession to his estate. Chapter Six deals with the customary administrator, including his appointment, rights, duties, powers and liabilities. Part Pour is devoted almost exclusively to an examination of the various customary law rules of distribution observed by the different ethnic groups occupying the Mid-Western Region. In this part also, the rights and duties of the heir as well as those of a guardian are considered. Part Five covers testate succession. Chapter Thirteen deals with wills, gifts inter vivos and donationes mortis causa governed by the customary law. Chapter Fourteen discusses the general law of wills, i.e. wills in English form; and examines the purposes for which the machinery offered by the English Wills Acts has been employed by the Nigerian testator. The chapter concludes with suggestions regarding the enactment of legislation to deal with two aspects of the law of wills. One recommends that an attempt should be made to effect either complete integration or harmonization of certain requirements of the general law and the customary law relating to wills. The other calls for the placing of some restrictions on the testamentary powers of the deceased, or more precisely, family provision. A word must be said concerning the method used in collecting some of the materials presented in this work. Apart from several hitherto untouched publications, bearing on the Mid-Western Region, which have been presented here, there has been oral information collected on the spot from chiefs and other persons versed in the customary law in the Region. Their help in this connexion has been duly acknowledged at the appropriate pages of this thesis.