Under Hungarian Regent, Admiral Miklós Horthy, Hungary was an Axis state at the beginning of the European conflict.
While the majority of these Axis troops were Romanian, there were also significant contingents of Hungarians, Finns, Lithuanians, Latvians, Estonians, Italians, Slovaks, Croatians, Frenchmen, Danes, Norwegians, Belgians, and Spaniards.
After 30 August 1940, under Nagy, the Hungarian First Army took part in Hungary's annexation and occupation of northern Transylvania.
This army group was pushed back during the Battle of Târgul Frumos in May 1944.
On 28 December, a newly formed Hungarian government, under acting Prime Minister Béla Miklós, officially declared war against Nazi Germany.
Béla Miklós had been the commander of the Hungarian First Army from 1 August 1944 to 16 October 1944.