Shaka was excellent at expansion, but he was a militarist king, not a general. His talents were in Force Majeure politics and leadership. However, his downfall was something only an ineffective strategist would have permitted. I'd recommend "Washing of the Spears" as a decent history of the Zulu wars.
There was a minimal - indeed, a nearly nominal - force that went in to wipe him out at the end. Despite their modern weapons, they could easily have been defeated using an indirect strategy.
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Sorry; I'd missed the earlier question about Lee. The answer is that the manner of his fight and the high discipline of his troops caused even his opponents to honor him and his people. The surrender at Appomattox was brilliant on both sides; I honor Chamberlain's role especially.


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