Europa is one of Jupiter's moons, and may have been chosen due to its possibility of harboring life.
The names of the missions are all of demons, hell's rulers, fallen angels and Djinns.
Europa was overrun by Fusion MOAs during the Fusion Moa Event. Prior to this, Europa was controlled by the Infested. Its current description implies that the Infested are slowly reclaiming it.
Prior to Update 11, Europa's description read: "The Infested are spreading throughout the Orokin Derelicts in this region". This implied that some of the Orokin Derelicts are located here, as well as Eris (which also had the same description).
Even before the current resource list was officialized, there was an issue with the drop rates on Europa which caused every resource pack to contain Rubedo despite other resources being listed in the mission select screen.
Prior to the Invasion mechanic being changed so that nodes did not change faction if they were lost by the defending faction, Europa was completely conquered by the Grineer during an invasion event.
Up until Update 9 Europa originally did not have a boss. When the Stalker was introduced, he was believed to be the new boss of Europa.