Martyrs at the hand of whom?
Some times God allows things in motion to happen to render a future result favorable to his plan.
Whether God uses a chess piece as a sacrificial pawn for the grand chest move in the future is also a consideration.
None the less they are martyrs for God's cause.
What would that mean to us today?
God will strategically offer up many chess pieces in play in the grand finale of his Master Check Mate move.
It would be incumbent that we boast of chess pieces in play and not those who had been sacrificed, for God's thoughts and ways are not our thoughts and ways.
I personally would pay attention to the Church Denomination that God has in play that he will use. I believe that it is not the two queens (Catholics and Orthodoxy), but it most probably will be a knight/horse chess piece that God will bring into centre board play. The point of the knight in play is to herd the remaining pieces to a centralised focal play. The knight becomes the rallying call for other remaining chess pieces to reinforce the move of the knight in synchronicity.
The martyrs are banked according to God but our focus should be on the chess pieces in play.
I believe the game of life is not about the past martyrs but about the present and future chess pieces in play.
So if we want to agree with the post, we need to contextualise that the martyrs of the past were predominantly Orthodox (original Queen), in order to weaken the Queen of the enemy (Roman Emperial church), so that it can one day be in God's possession used as a second queen (Catholics) for the future grand finale chess move.
Yet neither of the queens that God has at his disposal will be the main central player to bring the game to a head in centre play, but rather it will be a knight/horse that had been sitting quite in the background for a long time.
The team of the enemy are unbelievers and God's focal point is to initiate a Grand Final chess move in a rallying revival call through the insignificant knight chess piece and in this final play many will be sacrificed in the process.
If we truly want to know which denimination will have the greatest martyrs, then I opine that it will be the thousands of non denominational assemblies who have been readied by God to give their lives to Jesus and to immediately be with him.
God is the Grand Master player in Four Dimensional Chess.