How did ancient wars know how many troops the opponent had?

In ancient feudal society, emperors did not hesitate to launch wars to expand their territory, but besides strategy, numbers can be said to be the key to victory or defeat.

'The Art of War' once mentioned that 'Know yourself, know your enemy, and you can fight a hundred battles with no danger of defeat'. The most important thing in marching and fighting is to grasp the strength of both sides, so that the right decision can be made and implemented.

There were four methods for measuring enemy numbers in ancient times.

According to recorded sources, the ancients mainly relied on four methods to estimate the number of enemy troops.

First is to look at the traces, footprints of the kitchen, the most important thing in marching and fighting is to eat, so that the soldiers have the strength to win or lose against the enemy, in ancient times the kitchen was divided into a small team, so you only need to observe the enemy's kitchen. The number of people can be estimated; this can also be proven, horse hoof prints and soldier footprints can also be seen.

The second is to observe the smoke and dust that soldiers raise when marching, knowing that the more they march, the bigger the smoke and dust that rises, and vice versa, the smaller the smoke and dust, the fewer the soldiers. In ancient times, Zhang Fei (China) once deliberately ordered soldiers to tie tree branches to the tails of horses and deliberately pull them to create huge clouds of smoke and dust to mislead the enemy, making the enemy truly afraid.

Third is to look at the number of flags and drums, flags and drums are important command signals in ancient armies, to effectively command an army, a certain number of flags and drums must be placed in corresponding positions, so according to the number of both, you can roughly estimate the size of the entire army.

Fourth is to look at food and grass, as the saying goes, when the army does not move, food and grass come first, generally the army will bring 1, 2 months of food and grass to the battle. Therefore, by observing the amount of food and grass of the enemy, the upper limit of the enemy's number can also be estimated.

However, even if you master these 4 ways to calculate enemy troops, it is only for reference . After all, if the opponent is proficient in this method, it is very possible to become suspicious and play tricks on the opponent.