According to the Hindu Vedas and the Greek and the Roman laws...

According to the Hindu Vedas and the Greek and the Roman laws, the power of procreation was confined to men only, and hence family religions were the monopoly of men, and women had no hand in religious affairs except through their fathers or husbands. As they could not take part in the execution of religious ceremonies, they were naturally deprived of all family privileges. Hence, when the system of inheritance came into being, they were excluded.

The exclusion of woman from inheritance had other reasons also, one of them being that she was not fit to be a good soldier. In a society in which great value was attached to the heroic deeds and the power of fighting, and a warrior was regarded superior to a hundred thousand non-fighters, woman was deprived of inheritance, because she lacked the fighting capacity.

For this very reason, the pre-Islamic Arabs were opposed to inheritance by woman, who could not inherit as long as a male member of the family, howsoever distant, existed.

That is why they were greatly surprised, when the Qur'an expressly said: "For men is a share of what the parents and the near relatives leave, and for women is a share of what the parents and the near relatives leave, whether it be little or much - an appointed share', (Surah an-Nisa, 4:32) It so happened that the brother of Hassan bin Thabit, the famous poet, died in those very days, leaving behind a wife and several daughters.

His paternal cousins appropriated all his property and did not give anything to his widow or daughters. The widow complained to the Holy Prophet who called her deceased husband's cousins. They said that a woman was unable to carry arms and to fight the enemy. It was the men who defended themselves and the women. Hence, they alone had the right to inherit the property. Thereupon, the Holy Prophet conveyed to them the command of Allah, as revealed in the above quoted verse.

INHERITANCE OF AN ADOPTED SON The pre- Islamic Arabs sometimes adopted someone as their son. The adopted son like a real son, was considered to be an heir. The custom of adoption existed among other nations also, including the ancient Romans and the Iranians. The adopted son, being considered to be just like a real son, enjoyed such privileges as were not allowed to the lineal daughters. These privileges included the right of inheritance.

Similarly, marriage with the wife of an adopted son was prohibited. The Holy Qur'an abolished these customs.