Does it matter whether the biblical story of 'Cain and Abel' is true or not? Besides, aren't we of the same species and, therefore, brothers? Brothers have fought off their rival brothers. Jealousy and arrogance in man has led both sexes to all sorts of violence.
This ancient grudge existed between two Arabs, Hashim, great grandfather of prophet of Islam and his nephew, Umayyah, dating back to about 1400 years ago. Jealousy and arrogance in Umayyah cost him banishment, but when Hashim's grandson was recruiting followers, Umayyah, still bearing the old grudge, ostentatiously joined his cousin, buying time to strike.
Umayyah had two grand grandsons, Muawihah and Uthman. Muawihah, being literate, assumed the job of a scribe with his burgeoning cousin, prophet, who verbally recited messages to his audience, those with good memory power. On the other hand, Uthman, another grand grandson was elected as the third Caliph. One of Uthman's notable achievements was the compilation of the Qur'an into one single copy while destroying other versions.
Uthman never openly objected to the new religion, Islam, initiated by his remote cousin, but what lastly happened to him proves the contrary. He is comparable to Julius Caesar. Uthman, the principle third successor and a follower of the prophet, was murdered by Arab revolutionaries!
During the rule of Uthman, 23 years after the demise of the prophet, his warriors raided the entire defenseless towns and cities of the fallen Persian Empire, from India to North Africa. His warriors extorted vast amount of gold from residents who already believed in the same God. The rule of engagement was simple: if the inhabitants resist, attack, kill, confiscate their assets and take their young females as sex slaves.
In reality, Muawihah , the exiled guy, raised children that resolutely usurped power from the favorite cousin of Uncle Hashim. Muawihah successfully eliminated all close remaining relatives of the prophet, such as Ali, prophet's cousin & 4th successor, and Ali's sons etc.
Uthman was murdered because he was accused of violating the rules of Islam. However, the entire population of his time was forcefully converted to Islam without recourse to apostasy, the penalty of which is still death. His cousin Muawihah and his successors ruled half of the world under the auspices of Islam.
The following story is written by an authority, Khwaja Nizam al-Mulk , vizier, prime minister, of the Seljuq Empire, 1018-1092.
On that day, al-Mu'tasim, 833 -842, (another Arab Caliph), was drinking wine, (forbidden in Islam). His Chief Justice was attending! Caliph rose; went into a chamber; returned; sat down and resumed drinking. This withdrawing and returning repeated three times. After each absence, he also went to his private bathroom and performed Islamic ablutions. Then, addressing his Chief of Justice, he said, "You know what I was doing? F*** three captured virgin daughters of three infidels: the daughter of the Emperor of Rome, the daughter of Babak, (legendary Persian nationalist leader), and the daughter of Maziar, (another Persian nationalists, all defeated and savagely mutilated by him, the Caliph.)"