Joj Castl, Mand'alore te Cabur (Mandalore the Guardian), was Mandalore around 1000 ABY. His was a just rule and encouraged strengthening Mando worlds not only militarily but with heart, knowledge, and a sense of family not seen in almost a millennia. Few resisted the idea as it was an opportunity for regrouping and waiting for the opportunity for continuing the quest for Glory and Honor. Mandalorians still served as mercenaries. Those not in the field worked to improve the lives of all Mando. This became a renaissance for Mandalore and it's sister planets. Populations flourished. The Republic and other governments were concerned with another Mandalorian Expansionist Empire. Castl was the longest reigning Mandalore and the Mando worlds became strong. The Republic was correct...almost. Mandalorians were mercenaries and bounty hunters but as their worlds prospered, they stayed within their borders. They honed their skills and their knowledge. They expanded not in property but as a culture. Just don't mess with a Mando.