January 1, 2026: The Ukrainian army recently reorganized its forces into ten corps. In doing this Ukraine reduced the number of subordinate units a commander must deal with. Because of these reforms Ukraine was able to defeat Russian efforts to carry out offensives rapidly in Donetsk, Kharkiv, and Zaporizhzhia provinces. The corps organization enabled the Ukrainians to rapidly create formations of troops for offensive and counterattack operations.

Nine years ago Russia, in an effort to promote morale and national pride, Russia modified a 2008 reorganization to reconstitute the famous, during World War II and the Cold War, 1st Guards Tank Army. This revived unit was stationed in western Russia, the better to frighten European countries that were invaded during World War II, or threatened by it during the Cold War by the original 1st Guards Tank Army. The latest version was a showcase unit and the first to receive new tanks and other weapons as well as the best troops available.

The new 1st Guards Tank Army is actually remarkably similar to its World War II counterpart. Back then mechanized tank or infantry forces were based on brigades. These were organized into division-sized mechanized or tank corps. Thus the World War II 1st Guards Tank Army consisted of the 8th Guards Mechanized Corps with three mechanized infantry brigades and one tank brigade. The 11th Guards Tank Corps of three tank brigades and one mechanized infantry brigade. The 2015 version consisted of one tank division, with two tank regiments. There was one mechanized infantry division with one tank regiment, three mechanized infantry regiments, one independent tank brigade and one independent mechanized infantry brigade.

During the Cold War the 1st Guards Tank Army consisted of two tank divisions and one mechanized infantry division. All three divisions of the 1st Guards Tank Army had about the same number of troops, some 35,000 troops and about 300 tanks. All three versions had supporting troops, artillery, anti-aircraft, engineers, supply and so on.

The World War II era brigades had few support units and depended on the corps and army for supply, maintenance, artillery and so on. In 2008 Russia reorganized its army by replacing divisions with more self-sufficient brigades. When that change was complete several years later the combat forces consisted of 55 combat brigades, 33 mechanized infantry, four tank and 22 Spetsnaz, airborne or air assault units. These brigades were about half the size of American combat brigades and about a third of the personnel were conscripts who served for one year. The skill levels of troops in these brigades was much lower than for comparable troops in American or British brigades and elite brigades in French, German and some other Western forces. There were also 28 combat support brigades eight armed with multi-barrel rocket launchers like the U.S. MLRS, nine with short range ballistic missiles, ten with anti-aircraft missile systems and one engineer brigade.

Russia, like the United States, did not get rid of divisions as divisions, but they became a headquarters with some support units that could handle two or more combat brigades.