The beheaded saints were "made alive spiritually" while they were alive. After being killed, they are made alive physically called a resurrection. They are part of the first of two very large group resurrections.
They were beheaded because they were made alive in Christ,
Verily, verily, I say unto you, The hour is coming,
and now is, when the dead shall hear the voice of the Son of God: and they that hear shall live. Jn.5:25
It was meet that we should make merry, and be glad: for this
thy brother was dead, and is alive again Lk.15:32
yield yourselves unto God,
as those that are alive from the dead Rom.6:13
Wherefore he saith, Awake thou that sleepest, and arise from the dead, and Christ shall give thee light. Eph.5:14
This is the 1st resurrection.
Which is ignoring the future verb tense that mortals will be ruled over in the future past killing at Armageddon.
After our Lord returns, the redeemed are ruled by the redeemed,
And Jesus said unto them, Verily I say unto you, Thatye which have followed me, in the regeneration when the Son of manshall sit in the throne of his glory,ye also shall sit upon twelvethrones, judging the twelve tribesof Israel. Mt.19:28
And he said unto him, Well, thou good servant: because thou hast been faithful in a very little, have thou authority over ten cities.
No unbelievers will be alive at the timeframe of those verses. They will have suffered the second death in the lake of fire. Only after that will the New Heaven and new Earth take place.
The time frame of those verses is the the return of our King,
But those mine enemies, which would not that I should reign over them, bring hither, and slay
them before me. Lk.19:27