Reconnaissance-in-force in the context of "Military exercise"

The Mongol Empire invaded and conquered much of the Kievan Rus' in the mid-13th century, sacking numerous cities such as Ryazan, Yaroslavl, Pereyaslavl and Vladimir, including the largest: Kiev (50,000 inhabitants) and Chernigov (30,000 inhabitants). The siege of Kiev in 1240 by the Mongols is generally held to mark the end of the state of Kievan Rus', which had already been undergoing fragmentation. Many other principalities and urban centres in the northwest and southwest escaped complete destruction or suffered little to no damage from the Mongol invasion, including Galicia–Volhynia, Pskov, Smolensk, Polotsk, Vitebsk, and probably Rostov and Uglich.

The Mongol campaign was heralded by the Battle of the Kalka River on 31 May 1223, which resulted in a Mongol victory over the forces of several principalities as well as the remnants of the Cumans under Köten. The Mongols retreated, having gathered their intelligence, which was the purpose of the reconnaissance-in-force. A full-scale invasion by Batu Khan followed, with most of Kievan Rus' overrun in 1236–1238. The Mongols captured Kiev in 1240 and moved west into Hungary and Poland. The heavy losses suffered by the Mongols during the invasion period significantly weakened subsequent campaigns, preventing the ruin of the Holy Roman Empire and more western countries.

Hit-and-run tactics are a tactical doctrine of using short surprise attacks, withdrawing before the enemy can respond in force, and constantly maneuvering to avoid full engagement with the enemy. The purpose is not to decisively defeat the enemy or capture territory but to weaken enemy forces over time through raids, harassment, and skirmishing and limiting risk to friendly forces. Such tactics can also expose enemy defensive weaknesses and achieve a psychological effect on the enemy's morale.

Hit-and-run is a favored tactic where the enemy overmatches the attacking force and any sustained combat is to be avoided, such as guerrilla warfare, militant resistance movements, and terrorism. However, regular army forces often employ hit-and-run tactics in the short term, usually in preparation for a later full-scale engagement with the enemy when and where conditions are more favorable. Examples of the latter include commando or other special forces attacks, reconnaissance-in-force, or sorties from a fortress, castle, or other strongpoint. Hit-and-run tactics were also used by the lightly armed horse archers, typical of the Eurasian steppe peoples, who excelled at them. That holds especially true for such troops that were not part of a large army (such as scouting parties), but it was common to see them employed in such a way even as part of a major force.