[1] From Ukraine's independence in 1992 to 2003, the defense of the Crimean Peninsula was tasked to the 32nd Army Corps, numbering 12,000 troops.

[2] In February 2014 the Russian Federal Security Service organized anti-Ukrainian meetings and convinced several local anti-Maidan supporters to seize a series of ferry docks which in turn allowed 30,000 unmarked Russian personnel to cross the Kerch Strait at night.

Personnel loyal to Ukraine from the 501st, 1st, and 36th were merged to form the 36th Marine Brigade, with the 501st preserving their identity, command and logo as a highly autonomous battalion based out of Berdiansk.

[7] The State Bureau of Investigation (DBR) opened an investigation into the battalion's commanders, uncovering that Kostiantyn Bezsmertnyi had spread pro-Russian propaganda to his men, received payments from Russian intelligence, and defected with the condition that the battalion and officers would be transferred to the Donetsk People's Republic.

However, this policy was reversed after the release of Ukrainian POWs who interviewed members of the 501st and shared that the personnel were duped by their commanding officers, namely Bezsmertnyi and Mykola Biriukov, as well as several junior officers, were told that they were evacuating via a humanitarian corridor, and did not realize they were being sent to POW camps until after they were on busses.

[11] On June 29, 2023, the Battalion's "Gryphon" unit released a video of them using western anti-tank weapons to destroy Russian tanks.