Alexander the Great is excluded, because he's a bit too great.
I 'like' Frederick the Great. He managed not to lose against the combined might of Russia, France and Austria, helped transform Prussia into an economic powerhouse and the most important German state (discounting Austria), was tolerant(ish) of all faiths and was a champion of the Prussian enlightment. Noted politcal writer of his time and pretty good at the transverse flute as well by all accounts.
However, he was forced by his father to watch from a jail cell as his friend (and probably lover) was decapitated as punishment for his involvement in Fred's escape plot. Also, he was extraordinarily cold to his wife, isolating her from Prussian high society and on seeing her for the first time in many years allegedly the only words he spoke were: 'madame has grown fatter'
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