Oblique order

The oblique order is a military tactic whereby an attacking army focuses its forces to attack a single enemy flank. The force commander concentrates the majority of his strength on one flank and uses the remainder to fix the enemy line. This allows a commander with weaker or equal forces to achieve a local superiority in numbers. The commander can then try to defeat the enemy in detail. It has been used by numerous successful generals. Oblique order required disciplined troops able to execute complex maneuvers in varied circumstances.

In the oblique order attack, the commander of the army would intentionally weaken one portion of the line to concentrate their troops elsewhere. They would then create an angled or oblique formation, refuse the weakened flank and attack the strongest flank of the enemy with a concentration of force. Once the critical flank was secure, the commander would wheel the troops 90 degrees to roll up the enemy line, and the angled formation would continue to advance. The echelons not involved in the assault served the important function of holding the rival army in check by remaining defensive and threatening, thus offering protection to the attacking echelons by keeping the enemy force occupied. On occasion both commanders would attempt the same tactic (e.g.the Diadochi trying to replicate Alexander's tactics). The oblique order was a tactic particularly favored by King Frederick II of Prussia.

There were some dangers with attempting an oblique order in battle, namely the chance of opening up a fatal gap between the two wings, or that the two forces may completely lose contact. Moreover, the Frederician oblique order called for a long march, either through the night, or in the early hours of the morning of the assault, which meant that the advancing Prussian forces were almost always fatigued by the time they engaged their enemy. Another risky aspect of the oblique order was that it required total determination, as, once it was executed, the assaulting echelons would be deployed with no chance of being recalled.

Proper execution of Frederick's oblique order involved three main requirements. First, each officer needed to know exactly how to form a battalion from "line to column, maintain its place in the column, and then redeploy either normally, or en echelon for the final attack." The next two necessities were that the soldiers marched in close formation, and in step. Cadenced marching had not been used since the days of the Roman Empire; however, uncadenced marching, or 'route step', required loose marching order to ensure that the soldiers did not bump into each other, and the oblique order could not have been implemented in such unstructured formations. Lastly, for the oblique order to be successful the leaders of the opposing forces had to be unaware of the Frederician technique, which could be countered by a quick response from them; the attack required a confused enemy army incapable of a rapid change in their deployment. Frederick's oblique order was born of the desire to overwhelm a weak point in the enemy line, thus allowing a smaller Prussian force superiority on the battlefield.

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