Together with Václav Kopecký, Široký was an agent of the Soviet NKVD, whose task was to inform the Moscow leadership mainly about Gottwald's activities.

[4] After the end of the war, Široký was a member of the Presidium and the Politburo of the KSČ as well as its secretariat, making him one of the most influential men in Czechoslovakia.

[5] When Zápotocký died in November 1957, Široký carried out most presidential duties for a week until party boss Antonín Novotný was elected president.

[6] The charges would culminate in a trial in April 1954, where Husák and other leading Slovak politicians were sentenced to lengthy prison terms.

[9] Široký's party membership would be restored shortly before his death in 1971, during the period of normalization headed by his former political enemy, Gustáv Husák.