During the period of his internal exile, Friedrich became associated with the White House Comrades Association (Hungarian: Fehérház Bajtársi Egyesület), a right-wing, counter-revolutionary group, which originated from a secret society of intellectuals founded by dentist and well-known anti-Semitic political figure András Csilléry in 1916.
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.

After attempting to negotiate with the new moderate Social Democrat prime minister, Gyula Peidl, in an attempt to replace his government with a coalition where the Socialists would be forced to the background and removed, Friedrich tried to gain support for his project from the representative of the Entente.
Failing in both endeavours and fully aware of the conspiracies of the reactionaries, he decided to join the White House to control the plot.
The first meeting of the conspirators took place on 1 August 1919 and it was decided that they would take power on 5 August, before the possibility that the prime minister could reach an agreement with the Entente which would reinforce his power or that he would agree to form a new coalition cabinet with the middle class parties.
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 with the condition that the operation did not cause chaos and that the coup leaders acted promptly.

The conspirators who ended up supporting Friedrich were not politicians, but bourgeoisie (officials, university professors, dentists, etc.)
with radical right leanings (anti-Semitic, anti-democratic and anti-monarchical).
Their first candidate for prime minister was Gyula Pekár, a novelist of little success who was very close to the late prime minister István Tisza.
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.
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.
However, Joseph was unpopular with the membership of the White House because of his supportive role in the Aster Revolution.

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.
A White House spy informed Csilléry of the conversation's content.
Böhm's telephone call confirmed the counterrevolutionary forces' worst fears; the Allied representatives were willing to recognise Peidl's cabinet.
The leaders of the White House then felt that they needed to take power immediately.

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.
At the same time, they had occupied the Ministry of Defence without resistance.
After some protests, Peidl's cabinet agreed to resign under threats and with the coup plotters' promise that a coalition government would be formed.
Friedrich's participation in the coup was minimal, as he has always tried to resolve the situation by negotiation.
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
During the period of his internal exile, Friedrich became associated with the White House Comrades Association (Hungarian: Fehérház Bajtársi Egyesület), a right-wing, counter-revolutionary group, which originated from a secret society of intellectuals founded by dentist and well-known anti-Semitic political figure András Csilléry in 1916. 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.
After attempting to negotiate with the new moderate Social Democrat prime minister, Gyula Peidl, in an attempt to replace his government with a coalition where the Socialists would be forced to the background and removed, Friedrich tried to gain support for his project from the representative of the Entente. Failing in both endeavours and fully aware of the conspiracies of the reactionaries, he decided to join the White House to control the plot. The first meeting of the conspirators took place on 1 August 1919 and it was decided that they would take power on 5 August, before the possibility that the prime minister could reach an agreement with the Entente which would reinforce his power or that he would agree to form a new coalition cabinet with the middle class parties. 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 with the condition that the operation did not cause chaos and that the coup leaders acted promptly.
The conspirators who ended up supporting Friedrich were not politicians, but bourgeoisie (officials, university professors, dentists, etc.) with radical right leanings (anti-Semitic, anti-democratic and anti-monarchical). Their first candidate for prime minister was Gyula Pekár, a novelist of little success who was very close to the late prime minister István Tisza. 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. 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. However, Joseph was unpopular with the membership of the White House because of his supportive role in the Aster Revolution.
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. A White House spy informed Csilléry of the conversation's content. Böhm's telephone call confirmed the counterrevolutionary forces' worst fears; the Allied representatives were willing to recognise Peidl's cabinet. The leaders of the White House then felt that they needed to take power immediately.
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. At the same time, they had occupied the Ministry of Defence without resistance. After some protests, Peidl's cabinet agreed to resign under threats and with the coup plotters' promise that a coalition government would be formed. Friedrich's participation in the coup was minimal, as he has always tried to resolve the situation by negotiation. 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 
István Friedrich