Nikifor Grigoriev came from a peasant family. He was born in Podolsk governorate (according to another version, in Kherson governorate). He studied at the paramedic school in the town of Nikolaev. Since 1901, he was in military service. A participant of the Russo-Japanese War. Grigoriev graduated from the Chuguev Infantry Cadet School (1909). In 1912, he retired and worked as an excise official in Alexandria (Kherson governorate). A participant of World War I. Staff Captain (1916).

After the February Revolution, he commanded a training team of the 35th reserve infantry regiment (Feodosia), served in Berdichev garrison. A member of the Soldiers’ Committee of the Southwestern Front. Grigoriev supported the policy of the Ukrainian Central Rada, took part in the Ukrainization of military units.

In the summer of 1918, he quit the service in protest against the policy of Hetman Pavlo Skoropadsky. In October 1918, he led the uprising of peasants of the Elizavetgrad region. With a 200-strong detachment, he launched a guerilla war against the forces of the Ukrainian state and Austria-Hungary. He joined the armed forces of the Directorate of the Ukrainian People’s Republic (UPR). Grigoriev proclaimed himself “the Ataman [commander] of rebel troops of Kherson region, Zaporozhye and Tavria”, united 117 local guerilla detachments, and formed the Kherson insurgent division. In the autumn of 1918, he became close to the Ukrainian Socialist-Revolutionaries (Borotbists). In December, he defeated the consolidated detachments of Hetman Skoropadsky, White Guards, and German forces, and captured Nikolaev.

In early 1919, the French and Greek troops were permitted to expand their zone of control by the UPR Directorate and began their advance towards Kherson. On February 1, 1919, Grigoriev contacted the command of the Workers’ and Peasants’ Red Army to propose joining forces to fight the UPR and the interventionists. In February 1919, in Kharkiv, Grigoriev’s forces joined the 1st Zadneprovsk Ukrainian Soviet division as the 1st Brigade. Grigoriev commanded the capture of Kherson, Nikolaev, and Odessa. He was appointed as the military commandant of Odessa, and was among the first awardees of the Order of the Red Banner.

At the beginning of May 1919, he violated the order of the Red Army’s command to assault Romania. 4–6 May saw Grigoriev’s troops perpetrate pogroms in Elizavetgrad and Alexandria, which resulted in 1.5 thousand casualties. On May 8, he called for an uprising against the Bolsheviks under the slogan of Ukraine’s independence. In Yekaterinoslav, Ochakov, Nikolaev, the sailors and soldiers responded to the call. At the end of May, the Red Army forces inflicted a number of defeats on Grigoriev’s forces.

July 1919 saw the remaining detachments unite with Nestor Makhno. Makhno became the Head of the Insurgent Council, and Grigoriev became the commander of the troops. Their joint action lasted three weeks. On July 27, 1919, he was accused by the Makhnovists of connections with Anton Denikin and shot.