Multiple studies have been conducted using comparative phylogenetic analyses as a means to clarify the evolutionary relationships between Bacillus species, resulting in the transfer of species into numerous novel genera such as Alkalihalobacillus, Brevibacillus, Solibacillus, Alicyclobacillus, Virgibacillus and Evansella.

[5][1] Priestia is named after the British microbiologist Fergus G. Priest (professor, Heriot-Watt University, Edinburgh; 1948–2019) for his many contributions to the systematics and uses of the members of the genus Bacillus.

[1] Members of this genus are aerobic and found in diverse locations, such as soil, faeces, upper atmosphere, inner tissues of cotton plants, sea sediment, and the rhizosphere of willow roots.

P. aryabhattai is industrially important as it is resistant to arsenic and UV radiation, allowing for an affordable alternative to conventional, expensive, metal remediation technologies.

Two conserved signature indels (CSIs) have been identified through genomic analysis as exclusive for this genus in the proteins oligoribonuclease NrnB or cAMP/cGMP phosphodiesterase and DHH superfamily protein, and can be used to reliably differentiate this genus from other Bacillaceae genera and bacteria in molecular terms.