Ashkaran is an ancient language that was spoken in the kingship of Sephirah before it became the Kingdom of the Dead.
The only known speakers currently alive are Neshamah, Catherine Foundling and Masego. While Neshamah grew up speaking Ashkaran, Catherine and Masego gained the knowledge by ripping it out of soul echos of ancient sephirahns in Arcadia.
It is still used by the Dead King in Keter, the password to enter the palace of thrice Reflection was an Ashkaran word.
One of the names of Neshamah, Beiakim, is said to mean 'Child of Iakim' in Ashkaran.[1]