Fratricide.

If you think politics are strange now, check out this passage from William Cleveland's book " A History of the Modern Middle East": " During the first four centuries of Ottoman rule, the royal princes received military and administrative training as in the various provinces of Anatolia. Each of the princes was trained as if he would be the next sultan; each had an equal claim to the throne. When the reigning sultan died, the struggle for power began as the contending princes rushed toward Istanbul. The first prince to secure the support of the support of the royal court and the imperial guard in the capital city was proclaimed sultan. In order to prevent continuing rival claims to the throne, the Ottomans adopted the practice of fratricide; once the victorious prince had assumed the office of sultan, he ordered his brothers killed. This was a practical matter of state, and justification for the practice was encapsulated in the Ottoman political statement that " the death of a prince is less regrettable than the loss of a province."