The Northern Expedition which raged across central and Northern China from 1926 to 1928, was a monumental military campaign to unify China under the Kuomintang and bringing an end to the 'Warlord Era' which had dominated China since 1912.

The Expedition extremely led to the demise of the Beiyang Government and the Chinese Reunification of 1928.

The origins of the Northern Expedition began in 1925. In 1925, the May 30th Movement announced plans to strike and protest against Western Imperialism and its Warlord agents in China. During these tumultuous early years, the alliance between the Kuomintang (Nationalists) and the communists was questioned after the Zhongshan Warship Incident. The incident left Chiang Kai -Shek as supreme leader of the Nationalists. Further to this, Chiang doubted the nationalists' alliance with the Soviet Union and the Communists; he still needed aid from Soviet Russia. To this end, the Nationalists did not break the alliance at this time.

The sheer political and military power of central and Northern China since 1912 had been the Warlords. The initial targets of the Nationalists were Zhang Zuolin who controlled Manchuria, Wu Peifu 'The Jade Marshal' in central China and Sun Chuanfang in Eastern China.

Advised by the Japanese, White Russians and Westerners, the Head Quarters of the Expedition decided on the strategy of defeating the Warlords one-by-one.

In July 1926, Chiang proclaimed the National Revolutionary Army's strategy to the 100,000 men which made up the Nationalist Army. The NRA were far better trained, equipped and motivated than warlord Armies. Furthermore, the NRA was seen as a liberating and progressive force by ordinary people who had been persecuted by varying Warlord factions. This factor, combined with the training and motivation leaves little wonder as to how and why the NRA marched from the Zhu River to the Yangtze River in less than six months, swapping its ranks from 100,000 to 250,000.

In the wake of the annihilation of the Zhili Clique, the Nationalists decided to purge the Kuomintang of all communists. In Shanghai, thousands of Communists were executed while others were arrested and imprisoned.

The purge in Shanghai inevitably caused further disarray in the politically violent period. The Kuomintang split between left and right, and those on the left, led by Wang Jingwei, condemned Chiang's purges. Chiang established his own capital at Nanjing, and through the summer of 1927, the Nationalist Party and its military forces were in disarray.

The disarray of the Nationalists in turn cave the Warlords the opportunity to rebuild their forces and engage the weakened Nationalists. The initial plan between the loose Warlord alliances was to position their combined army of 100,000 men around the lower Yangtze, drive the Nationalists south and pursue them further south into the province of Guangzhou.

Opposing the Warlord armies were three Kuomintang armies, often referred to as 'Route Armies'. The first was north of Nanking, the second to the west of the first army and the third stationed in the south.

The Nationalists could afford to muster the equivalent number of men, but it was very divided by political and leadership tensions. Importantly, it was the element of surprise that cave the Warlords the advantage of attack, as an offensive by the warlords was not expected Chiang or any of his commanders.

On the 24th of July, the Warlord Offensive began

Sun Chuanfang's force which included Xu Kun's forces to turn through the surprised Nationalist forces. This claimed in the loss of Xuzhou in the Jiansu Province, north of Nanking. In turn, the second army stationed in the area, was forced to withdraw using the Long-Hai railway as an escape route. The other Nationalist forces began to retreat south toward the Yangtze as the Warlord juggernaut swept away any opposition.

Chiang, learning of the offensive, was astonished to hear that Xuzhou had fallen to the Warlords. Sacking the army's commander, Chiang ordered Xuzhou to be retaken. Attacking with his forces in that August, Chiang was defeated at a terrible cost. Following the defeat, Chiang resigned on the 6th August as head of the Nanking Government.

Following Chiang's resignation, this left Li Zongren as de facto leader of the Nationalist Government. Initially setting out to negotiate with the Warlord Faction, the talks broke down when one Warlord, supported by Wuhan dissenters attacked the warship on which the negotiations were taking place.
After this, the talks had succeeded in getting Wuhan to cooperate with the Nationalists. Wang Jingwei at the end of the talks ordered the purging of all communists with Wuhan. This claimed in a military coup by the communists in Nanchang, leaving over 8,000 Nationalists dead.

In late August, the Warlord Army, now close to the Yangtze, launched an all-out attack on the Nationalist Forces. The First Route Army was poorly mauled while defending the city of Longtan which was vital to the supply of Nanking via Shanghai. The mountain of Wulongshan became another Verdun as Nationalist forces held out far longer than expected. Knowing the strategic importance of Longtan, Nationalist reinforcements entered the fray and pushed back Warlord contingents. On the 30th August, the whole Second Route Army attacked Longtan, and by the late afternoon had recaptured the city. The Warlord armies suffering heavy losses, fled back across the Yangtze River.

The period following the retaking of Longtan saw the Nationalists regroup and reorganization, once more under the command of Chiang Kai- Shek. The Wuhan Government, bowing to pressure, reconciled their position with the Nationalists and merged with the Nationalist Government.

On December 12th, the Nationalist forces, after re-capturing most of the territory lost that summer, captured Xuzhou.

The re-organization of the Nationalists was the death blow to the Warlord Armies. Sweeping across the remains of Sun Chuanfang's and Xu Kun's Zhili Clique forces, the Nationalists reached the yellow river by mid-April 1928.

In this period, Yan Xishan declared his intentions of capturing Beijing. Knowing it was best to evacuate, Zhang retreated north and was allegedly assassinated by Japanese conspirators.

In looking at the outcome of the Northern Expedition, today, it is viewed positively as it ended a period wracked by civil war and started a period of effective government. Despite this, the expedition did not fully resolve the issue of the warlords, as many still had large armies that served their needs, not those of China.

The Communists at the time, criticized Stalin for relying on the 'bourgeois' figures of the nationalists who had betrayed the peasant workers.

It is important to note that out of all the conflicting factions, the only one which was destroyed was the Zhili Clique. A large number of Warlords and varying factions remained and in some cases due due to their alliance with the Nationalists. The Warlord factions that worked for the Nationalists merely won Nationalist uniforms and verbally shouted the party doctrine.

The main struggles between the Nationalists and the Warlord factions would claim more lives during the following decade. This in turn would prove to be a problem for the Kuomintang during World War 2 and the Civil War.

Overall, Chiang earned the most from the campaign. Making the military superior to the party leadership, which enabled Chiang to become dictator.