The Ottoman Interregnum
After the conqueror Timur shattered the Ottoman army and captured the sultan himself, the sultan's sons fought an eleven-year civil war for the throne that nearly ended the young empire before one brother reunited it. To prevent such ruinous struggles, later Ottoman law would permit a new sultan to have his own brothers killed on accession — trading fratricide for a clear line of succession. It is the succession crisis in its rawest form: where no clear rule of inheritance exists, the throne is settled by blood.
The orderly transfer of power fails because no rule or claimant is accepted as legitimate.