The BOSS series was founded in 1995 under the regulations of the RAC Motor Sports Association and raced mainly in Great Britain. Later renamed European BOSS (shortened by the competitors to EuroBOSS) following the involvement of Paul Stoddart's European Aviation and their expansion into European circuits. It mainly saw grids of around 12–15 cars but on occasions dropped as few as five cars have competed. Common EuroBOSS entries included Formula One machines from Benetton, Jordan, Tyrrell, Minardi and on occasions a V12 Ferrari has appeared. Other frequent entrants are Lola and Reynard CART chassis, the 1997-2002 Panoz (aka G-Force) and Dallara IndyCar chassis, and starting in 2012, the 2003-2011 Dallara and Panoz Champ Car chassis after the new INDYCAR formula begins. The Panoz Champ Car DP01 chassis from 2007 is also now legal.
After the 2009 season, drivers Marijn van Kalmthout, Klaas Zwart, Henk de Boer and Frits van Eerd decided to split off and organize their own race series. For 2010 EuroBOSS and BOSS GP both existed. EuroBOSS saw small fields and decided to cancel the last 3 rounds. BOSS GP, on the other hand, flourished with many drivers making the switch to the new series. Subsequently most of the entries have been recent secondary level single seaters such as GP2 cars and Renault World Series cars with a small number of Formula 1 cars. As of 2013 two rounds of the BOSS GP series form an official German championship sanctioned by the DMSB.
Over the years the classes have been updated. Nowadays relative new cars like the Dallara GP2/08 (GP2), Dallara T08 (WSbR and Lola B05/52 (A1GP/Auto GP) are allowed in the series. For 2010 EuroBOSS allowed the Tatuus N.T07 International Formula Master car to race in the series. The car was never allowed in the BOSS GP series.