Inheritance because of the oath of allegiance

وَلِكُلٍّۢ جَعَلْنَا مَوَٰلِىَ مِمَّا تَرَكَ ٱلْوَٰلِدَانِ وَٱلْأَقْرَبُونَ ۚ وَٱلَّذِينَ عَقَدَتْ أَيْمَٰنُكُمْ فَـَٔاتُوهُمْ نَصِيبَهُمْ ۚ إِنَّ ٱللَّهَ كَانَ عَلَىٰ كُلِّ شَىْءٍۢ شَهِيدًا

To (benefit) every one, We have appointed shares and heirs to property left by parents and relatives. To those, also, to whom your right hand was pledged, give their due portion. For truly Allah is witness to all things.