of Operation Barbarossa by several weeks and may have contributed to its failure. The game was finally published in 1979 as Marita-Merkur, named after German operations Marita and Merkur carried out during that campaign. However, it was published as a stand-alone game; by this time the Europa concept of covering the entire European theater had evolved, and the plan called for publishing a series of stand-alone games that provided Europa material, but concentrated on a single campaign and left most of the link-up issues to be addressed by future publications. The series also grew to cover such topics as the Spanish Civil War, which, though not strictly part of World War II, helped with the map coverage and provided a basis for what-if scenarios, had the various campaigns and battles of World War II gone differently in the games than the historical outcome. The plans for the series evolved somewhat over the four decades of its existence, but can be approximated as follows. The various games traditionally been identified as "Europa Game X", where X is a Roman numeral. Since some of the games have been published under different names for their various editions, the list given here describes the subject matter for each game and breaks out the individual titles as bullets. Many titles have unofficial but commonly used acronyms, given in parentheses after the title. Acronyms for the games' publishers are given as well. Several of the games listed here have had separately published "refit kits" for corrections and minor upgrades, and in some cases those have been included in later printings of the games. Their Finest Hour is the most extreme example of this, with both defective maps and numbers of counters needing to be reprinted. Some games have also been reprinted with new box art. Such details are not shown here. Europa I - The German invasion of the USSR and the Soviet riposte, 1941-1942. Drang Nach Osten! (DNO), GDW 1973. Primarily used German sources for OB information, and had rudimentary maps (by later standards). Fire in the East (FitE), GDW 1984. OBs and maps were thoroughly revised, utilizing more recently published material on Soviet forces. Total War (TW), HMS/GRD (not yet published). The final revision for this title. Maps and counters were released to those purchasers who chose this option at the end of 2012. Europa II - The Eastern Front, 1942–1944 Unentschieden, GDW 1973.