To the left is a very detailed map of the expeditions, click on thumbnail to open a bigger version. Size is 145 KB.
Northern Expeditions
Critique of the Northern Expeditions began soon after. Chen Shou concluded his biography of Zhuge Liang with the famous comment that while he was an outstanding political and military administrator he was unable to make appropriate changes in strategy. The continuous unsuccessful efforts to seize Longyou reflected his strategic inflexibility. Wang Fuzhi (1619-92) notes that the initial mobilisation and advance from Hanzhong in 228 created a perilous situation for the Wei court because it was unexpected. However, it was not followed through to success by the seizure of Chang'an because Zhuge had a limited strategic goal. In fact, the contrast between the two proposals of Zhuge Liang and Wei Yan in the first Northern Expedition has remained a focus of controversy and criticism among historians. Wei's numerical superiority could only be reversed by using some sort of a stratagem at the outset. Wei Yan's proposal of a surprise attack was feasible because such a manoevre had been used successfully during the Chu-Han Wars by Han Xin (206 BC).In the opinion of Wang Fuzhi, the goal of the Northern Expeditions was not to capture Chang'an at all, but to secure the Longyou region, which could provide back-door access to the Shu plain. It was a limited war for a limited strategic goal: the enhancement of the defensive posture of the Shu state. Others motion at a similar idea, that the expeditions were a means of keeping the enemy off balance using flexible tactics of advance-retreat. This is supported by the fact that Zhuge Liang also calculated his opportune times of advance and retreat. Only on one occasion, at Jieting, did the Shu army leave the battlefield not completed intact. Additionally, it is pointed out that except for two expeditions, Zhuge Liang's army never exceeded 50,000, a comparatively small force not capable of occupying the Northwest.
However, one must wonder at the wisdom of such a policy. It would seem from the evidence in the third Northern Expeditions that the defender had the advantage in the battle for Longyou and the Shu offensives served only to drain it of manpower and exaust its economic resources. A defensive policy may have been much more benefitial. The third Northern Expedition, with the invasion of Wei forces, showed the tactical advantages a defender had in terms of terrain if he was prepared. Despite all his tactical brilliance and inventiveness, such as the use of 'wooden oxen' and 'flowing horses' as well as the Bazheng formations, Zhuge Liang never suceeded in his Northern Expeditions. On the battlefield he demonstrated tactical skill and flexiblity, yet the ambiguity surrounding the purpose and strategic goal of his expeditions is perplexing. He seems to have disregarded the admonition in the Art of War to avoid weakening the nation by constant and fruitless campaigns. It is this dichotomous judgement of his performance, some positive some negative, that provides a realistic understanding and appreciation of his military career.