Returning to Hungary after a successful escape through Spain and Italy, he volunteered and served in the Austro-Hungarian Army, in the artillery, with the rank of lieutenant, and fought at the Uzsok Pass in Carpathian Ruthenia.

[3] During the Aster Revolution at the end of World War I, he led large protests at the Royal Palace of Budapest to demand the appointment of the Károlyi government; he actively participated in and was wounded in the so-called "Battle of the Chain Bridge" on 28 October 1918.

[5][4][3] Following the formation of the government on 31 October, he was appointed Secretary of State for War in Károlyi's first cabinet on 1 November,[4][3] which came under his control because of the small size of his superior, minister Béla Linder's entity.

By contrast, Friedrich, as a prominent member of the moderate wing, rejected Károlyi's "naive" foreign policy and sought to set up a powerful army under the old leadership of military officers, contradicting Linder's pacifist manifesto.

[9] In the coming decades, several former colleagues, including Lajos Varjassy, Oszkár Jászi and Mihály Károlyi himself regarded Friedrich as a traitor, who had joined the reactionary forces, abandoning the cause of the short-lived liberal democracy in Hungary.

Initially sceptical, Friedrich refused to join them and worked closely with Lovászy and Bartha to bring together the formation of a new government after the expected collapse of the Kun regime.

[17][18] The conspirators communicated their plan to Guido Romanelli, the representative of the Entente in the capital, who rejected it, and the commander of the Romanian occupation troops, who approved it[13] with the condition that the operation did not cause chaos and that the coup leaders acted promptly.

[14] A few days later, Friedrich recommended his friend Márton Lovászy to hold the position of prime minister, however the leadership of the White House objected it on ideological grounds.

[16] On 4 August 1919, Friedrich led the monarchical delegation that persuaded Archduke Joseph of Austria, who had "universal prestige" in Hungary, according to Gusztáv Gratz, to travel to Budapest that night to carry out a coup that would overthrow the government of Gyula Peidl, controlled by the trade unionists.

[20] On 5 August, Vilmos Böhm, envoy to Vienna, phoned Budapest to inform his government of his meeting with representatives of the Entente Powers, where they accepted a moderate reorganisation of the Peidl cabinet instead of establishment of a grand coalition.

[21] With the control of the police and some of the military units in the capital on 6 August 1919, that afternoon members of the White House, most notably General Ferenc Schnetzer and Jakab Bleyer, arrested Károly Peyer, the Minister of the Interior, learning that the rest of the cabinet was meeting in council at the Sándor Palace, where they were detained by the coup plotters.

Historian Eva S. Balogh argued that he wanted to re-establish the early phases of the Károlyi regime, yet exclude the later shift that led to the Social Democratic Party having more influence in the affairs of the state.

[24] Following the success of the coup, which counted on the Romanian neutrality and the tacit support of the British and the Italians,[19] on 7 August 1919 Friedrich was named prime minister while the archduke became regent.

[7][19][25][21][13] After a one-week transitional period lasting until 15 August, his cabinet was composed primarily of former members of the government of Prime Minister Mihály Károlyi, belonging mainly to the more conservative wing of his Independence Party, which had split during his rule.

[19] The neighbouring states, fearful of a restoration of the Habsburgs, supported the French position and showed their opposition to the appointment of Archduke Joseph.

[4][13] On 23 August, the Archduke decided to resign the regency before opposition from the powers;[34] Friedrich thus lost one of the pillars of his government and the post of head of state remained unfilled.

[35] Militarily limited, Friedrich tried to politically underpin his government during August and September with successive modifications of the cabinet, first to the left and then to the right, without thereby achieving the recognition of the Entente.

[37] This party, created in October, brought together important politicians from the northwestern territories of Hungary, the Catholic Church and certain refugees from Transylvania, such as those grouped around István Bethlen and Pál Teleki.

[43] On 17 November, the Friedrich cabinet imposed Prime Ministerial Decree ME 5985/1919 which established universal suffrage by secret ballot to all citizens (including women) over the age of 24.

[45] Friedrich remained in office as Prime Minister until 24 November,[36] and then transferred to the Ministry of Defence[42] until 15 March 1920, a position of little significance given that the troops obeyed only Horthy.

[42] It was led by Károly Huszár, of little political stature and with few followers, elected as a result of the rejection of the candidacy of Horthy and his supporters to that of Albert Apponyi.