Where does “Nikolaos” come from?

Nikolaos (English) comes from Greek Νικόλαος, from Ancient Greek Νῑκόλᾱος — Nicholas.

Ancestry of “Nikolaos”, step by step

Step	Language	Word	Meaning
1	Greek	Νικόλαος	—
2	Ancient Greek	Νῑκόλᾱος	Nicholas