Where does “Kjartanía” come from?

Kjartanía (Icelandic) comes from Icelandic Kjartan, from Old Norse Kjartan, from Old Irish Muirchertach.

Ancestry of “Kjartanía”, step by step

Step	Language	Word	Meaning
1	Icelandic	Kjartan	—
2	Old Norse	Kjartan	—
3	Old Irish	Muirchertach	—

Kjartanía — Etymology, Origin & Word History | Etymology Explorer