There are many places in the world named Newcastle. At one time they may have had castles. Some still do. Not all of them are English-speaking.
There were new castles in many different countries resulting in names such as Shinshiro, Neuchatel, Neuburg, and Nove Hrady. And some Newcastles were named after other Newcastles or individuals bearing the name Newcastle.
Not all are cities, some are towns or even villages. One is an army settlement. One is a star.
They all shine brightly in their own way.