I might also add that General Tso's is not in "almost every Chinese restaurant in the world". Wikipedia is obviously not always the greatest source, but the start of the article kind of hits that point home: "General Tso's chicken is a sweet, slightly spicy, deep-fried chicken dish that is popularly served in most Chinese and Asian themed American restaurants."

Bolding mine.

General Tso's is a part of the 'American Chinese' culinary tradition, and really isn't that common outside of American chinese restaurants, as well as the many Chinese restaurants in the US that cater more towards Chinese Americans and internationals that tend to be more based in traditional cuisine.

Zuo Zongtang was a Qing Dynasty official, who was recruited by future Governor-General Zeng Guofan to serve as a general in the Xiang Army, a force raised by scholar-landowners to suppress the Taping peasant rebels. He cleared the rebels from the provinces of Hunan, Guanxi, Zhejiang and Fujian, and was appointed governor general of the latter two provinces after the war. As Commissioner of Naval industries, he founded China's first modern shipyard and naval academy. He was transferred to the governor-generalship of Shaangan in the north, where he put down another rebellion against the Qing, the Dungan revolt, and later the Nian Rebellion. He served a succession of prestigious posts, being named Grand Secretary, being given a seat on the Grand Council, with his last assignment being overseeing coastal defenses in Fujian during war with France.

Nothing to do with chicken.

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