The ideal, however, and the reasons for that ideal, which have guided many modern States in basing their constitution upon a doctrine of complete separation have arisen from bitter past experience. In the constitutions like that of England centuries ago, the ultimate combination of all authority in the person of the King, had lead to many evils culminating in a Civil War, ending in the execution of one king, and a bloodless Revolution leading to the abdication or expulsion of another king. The arrangement which was evolved thereafter has been kept in conformity with the genius of the British people, not so much by a written Constitution, as by evolving constitutional conventions, supported by centuries of usage. And these have become even more sacred than the written word in a written constitution.