https://www.biblestudytools.com/dictionary/mark-of-the-beast/

Dea 59; Herodotus 2.113). Third Maccabees 2:29 records an incident in which Jews were branded by Ptolemy Philopator I (217 b.c.) with the Greek religious Dionysian ivy-leaf symbol. The "mark" on Cain in Genesis 4:15 is rendered by semeion [shmei'on] in the Septuagint, the term for "sign." Paul's reference to his bearing in his body the "marks" of Jesus ( Gal 6:17 ) utilizes stigma [stivgma], not charagma [cavragma].

The contextual significance of marking those who worship the beast may be accounted for by noting how this motif answers to the seal on the foreheads of those who worship the Lamb ( Rev 7:3 ; 14:1 ). This contrast is particularly noted in 20:4, where those who are martyred for the Lamb are resurrected to reign with Christ. The mark and seal well image the two earthly groups who dominate the narrative.