Ottoman sultans had a legal right to execute all their brothers

In the 1470s Sultan Mehmed II codified a law letting a new sultan kill his brothers 'for the order of the world,' to head off succession wars. Mehmed III enforced it most brutally in 1595, having 19 brothers and half-brothers strangled with a bowstring on his first day as sultan. The practice ended only in 1603, when Ahmed I spared his half-brother and switched to lifelong confinement instead.

— Caroline Finkel, Osman's Dream: The Story of the Ottoman Empire — 2005; chapters on Ottoman succession and the House of Osman
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