Osaul or osavul (aide-de-camp). A military and administrative official in the Hetman state. The hetman usually appointed two general osauls as his closest military aides. Each Cossack regiment had two osauls who oversaw all regimental military matters (except the artillery), such as training, armaments, and supplies. In peacetime they took part in the civil administration of the regiment's territory. Company osauls had the same responsibilities on the company level. There were also osauls with special functions, such as the osaul of the state's General Artillery, who assisted the general quartermaster, and the osauls of mercenary infantry regiments and companies. The Cossack starshyna of the Zaporozhian Host also included an osaul. After the abolition of the Hetman state and the Zaporozhian Sich the osauls of the Cossack regiments incorporated into the Russian imperial army were equal in rank to infantry captains and cavalry troop commanders.
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