Battlegroup The Battlegroup was a level of command and organization in the Imperial Army , replacing the Divisions that had been widespread in sector and planetary forces under the Old Republic , and comparable to the Legions found in both the Grand Army of the Republic and the Stormtrooper Corps . Organization and usage . A typical Battlegroup consisted of four Regiments , and four Battlegroups in turn formed a standard Corps . Although precise numbers varied depending on the specific type of unit , the overall strength of most Battlegroups was on the order of roughly 15 , 000 men , including a little better than 10 , 000 front - line troops . A Battlegroup was committed only for major offenses against a known concentration of enemy resistance . During the first years of the Empire , a Battlegroup was composed of 8 , 192 troopers , and was composed of four regiments . A Battlegroup ' s commanding officer ( CO ) was typically at least a High Colonel , although it was possible for the CO to be as senior as a Major General ( the 1st Tapani Assault Battlegroup based on Tallan was one such example ) . A Battlegroup had the usual principle staff of five officers ( SG1 to SG5 ) , but in addition the SG5 ( Battlegroup " Headquarters " officer ) had a 4 - man " substaff " ( SG51 to SG54 ) . In addition there were 188 support personnel and two security platoons of 76 troopers for a total of 274 personnel . A battlegroup could also be augmented per their Order of Battle ( OB ) , in which case the additional units were commanded by the battlegroup ' s second - in - command . Line Battlegroup . Battlegroups with three line and one assault regiment were considered “ line ” formations . However , in the wake of the Battle of Tiems this unit was considered obsolescent as the Rebellion grew in strength . Within the military there was much debate about converting all line battlegroups into assault battlegroups , but resource and reorganization difficulties prevented any wide - spread changes . A line battlegroup had 10 , 219 troopers , 4191 support personnel , 511 repulsorcraft and 53 heavy tanks . It could be augmented with two artillery regiments , a fourth line regiment and a repulsorlift regiment . Assault Battlegroup . Also known as a reinforced battlegroup , assault battlegroups consisted of two line regiments , an assault regiment and an armored regiment . These formations were seen as a good mix of offensive and staying power . They had 10 , 210 troopers , 4 , 680 support personnel , 676 repulsorlift vehicles and 212 tanks . Fully augmented it had an artillery regiment , two additional assault regiments and a repulsorlift regiment . Armored Battlegroup . Armored battlegroups were used to attack the enemy when they had several concentrations of strength spread over a sizable area . With four armored regiments , two vanguard and two line , the battlegroup could hit these concentrations in succession one or two at a time . There were 10 , 090 troops , 6 , 256 support personnel , 1 , 132 repulsorlift vehicles and 318 tanks in a battlegroup and it could be quickly doubled in size with four more regiments thanks to augmentation . Mobile Battlegroup . A mobile battlegroup was composed of three repulsorlift regiments and one line armor regiment for a total strength of 10 , 248 troops , 5 , 858 support personnel , 1 , 342 repulsorlift vehicles and 265 heavy tanks . The advantage of this battlegroup was its speed : On planets where the Rebellion held areas close to the Empire ’ s , or the area was sympathetic to the Rebellion , this battlegroup could quickly respond to any incursions or perform it ' s own lighting attacks . It was augmented with an artillery regiment , two more repulsorlift regiments and a second armor regiment . Auxiliary Battlegroup . Unlike traditional battlegroups , auxiliary battlegroups had no commander and did not operate as a unit . This battlegroup was merely a concentration of available resources for their Corps commander and was composed of three CompForce regiments and a Ground Support Wing . In total the battlegroup had 7 , 674 troopers , 2 , 456 support personnel , 390 repulsorlift vehicles and 40 TIEs . If needed it could be augmented with three line regiments and a repulsorlift regiment . Ground Support Wing . The Army insisted on its own wing of support fighters for ground missions , while the Navy wanted to keep control of its TIEs . The result was this downsized wing of 40 TIEs organized into ten flights . Six flights made two squadrons of TIE / LNs , while three flights made a TIE bomber squadron and one flight of TIE / fcs served as spotters . These wings were also stationed in prefabricated garrison bases . The wing had forty pilots , twenty - five sensor techs , twenty - five controllers and one hundred and ten ground crewmen . History . Battlegroups were usually deployed in full strength in situations where a sizeable enemy force had to be destroyed in the field : they were capable of stand - alone operations where a well - organized military resistance controlled an area of a planet , and they also served as the primary tactical subdivisions of a Corps deployed for a full - scale planetary conquest campaign . Of course , not all Battlegroup deployments were for offensive operations , and not every operation required a full Battlegroup . For instance , the 1st Tapani Assault Battlegroup at Tallaan were the primary Imperial Army presence in Tapani sector , representing a largely defensive deployment that due to political considerations nevertheless warranted a Major General in command . And in all Battlegroups , individual Regiments or Battalions could be detached to deal with low - level insurgency or a specific focused target , or to support a Navy operation — although Imperial tactical thinking did restrict the use of Armor Regiments to full - scale Battlegroup offensives .