[2] The British military attaché to the Russian Army during the war claims that Yanushkevich owed his high position largely to his skills as a courtier and was rumoured to have found favour with the tsar when serving as a captain of the palace guard.

Sukhomlinov’s practice of appointing officers unlikely to threaten his own position, and only for a short period of time, to the post of Chief of the General Staff – ‘[He was]...chosen in the usual Sukhomlinov way to prevent anyone dangerous from taking over the job, and surviving in it from sheer force of characterlessness.’[4] Historian David R. Jones is less harsh in his assessment, pointing out that whatever his shortcomings Yanushkevich was a supply expert whose ideas were incorporated in the 1914 field regulations.

According to Stone both he and the Supreme Commander, Grand Duke Nikolai Nikolaevich, were mere figureheads—command of the Russian armies was effectively exercised by the ostensible third-in-command, Quartermaster-General Yu.

[7] The deeply anti-Semitic Yanushkevich, however, played a leading role in the savage pogroms and deportations to Siberia of Jews, Muslims, and ethnic Germans that accompanied the so-called "Great Retreat" of 1915.

At the insistence of Grand Duke Nikolai Nikolaevich, Yanushkevich continued to serve as his chief of staff after the latter's dismissal as supreme commander and appointment to the post of Viceroy of the Caucasus.