A “martyrology” is a listing and/or history of martyrs of a particular group. Catholics have the Roman Martyrology, for instance, and local ones such as Martyrologium Hieronymianum.
On Yom Kippur we have Eleh Ezkereh, “These We Remember,” which is often referred to as the Yom Kippur Martyrology. This is the passage we read on Yom Kippur, as part of the Musaf service, that describes in graphic detail the torture and death of the ten rabbis at the hands of the Roman Empire under Emperor Hadrian two thousand years ago. (See page 337 of the Mahzor Lev Shalem.) We go on through the Spanish Inquisition, and then the Holocaust.
The original poem was written in medieval times; the rest has been added. (Interestingly, it is followed on Yom Kippur by the Avodah service, which is a throw-back to the Temple times with priestly pageantry and such.) The Martyrology describes the murders as occurring one after the other, but historic records show some time between them. Martyred were: Rabban Shimon ben Gamliel, Rabbi Yishmael ben Elisha haKohen Gadol, Rabbi Akiva, Rabbi Haninah ben Teradion, Rabbi Hutzpit the Interpreter, Rabbi Elazar ben Shamua, Rabbi Hanina ben Hakinai, Rabbi Yesheivav the Scribe, Rabbi Judah ben Dama, and Rabbi Judah ben Baba. They say Rabbi Akiva, a big proponent of the Shema, recited it as he was tortured, telling his students that it was a joyous thing to be able to glorify the Holy One, even through pain and upon one’s death.
There is a recent trend to consider all those who died for being Jews as “martyrs,” that they have died “al kiddush hashem” in sanctification of God’s Name. There is a striking Wikipedia page, “Timeline of Anti-Semitism,” which certainly references many martyrs.
As some say at this time, “.אֵלֶּה אֶזְכְּרָה וְנַפְשִׁי עָלַי אֶשְׁפְּכָה. כִּי בְלָעוּֽנוּ זֵדִים כְּעֻגָה בְּלִי הֲפוּכָה” “These I remember and pour out my soul. How the arrogant have devoured us, like an unfinished cake.”