Diadochi name question

[Krusader]

From the translated works of Polybios at least (and I think Livy too and other authors), the Seleukid kings were refered to as Kings of Syria. Then again the Seleukids refered to Syria as Seleukis.

Honestly, Seleukeia or Syria would be what I'd personally go for.

Kassandros' empire was Makedonia, while Lysimachos' empire was refered to as kingdom of Thrace apparently.