The Messerschmitt Bf-109 was a German fighter developed in 1935 and was the backbone of the Luftwaffe for the entirety of the Second World War. The Bf-109 first saw combat over Spain during the Spanish Civil was when it was being flown by the Condor Legion. By September of 1939 it became the Luftwaffe main fighter replacing all the older Bi-planes. The Bf-109 was used extensively during both the Invasion of France and Poland. The 109 proved effective against French M.S 406s, Hawker Hurricanes, and P-36s, but found it difficult to fight French D.520s and Supermarine Spitfires.
After the fall of France the Bf-109 was used again during the battle of Britain this time with mixed results. The Bf-109 did not have the range to escort German bombers over the channel nor did they have the maneuverability to fight the Spitfires. Despite these set backs the Bf-109 went to to fight in North Africa, Russia, and Europe. The most common variant of the 109 was the F variant. Many Germany fighter aces got their titles while flying Bf-109.
In the Anime
In the Anime the Bf-109 presumably saw action over Livonia and Thermidor with the E-3 variant. The 109 was used in the Invasion of Eylstadt, early on in the war Izetta was able to shoot down a flight of Bf-109E-3s with an Anti-tank rifle.
During the battle to sink the Graf Zeppelin class aircraft carrier Drachenfels. The Bf-109T variant was used, the T was the only version of the 109 that was cable of preforming Carrier takeoff and landings. (In reality this variant never made it past the prototype stage due to infighting between the Kreigsmarine and Luftwaffe.)
The Bf-109 was used during the fall of Eylstadt and the final battle between Izetta and Sophie.