Zhentarim

The Zhentarim are a Mercenary company that operate throughout the world, their headquarters based in the Western Heartlands of the mainland. They provide some of the best trained soldiers and guards available for hire anywhere, as well as more expertly skilled agents and spellcasters for specific goals. In Port Nyanzaru, the Zhentarim are the most popular mercenary force employed as guards for many of the noble and rich families, including many of the Merchant Princes themselves.
Mercenary work is closely controlled by the Prince Jobal, and the Zhent leadership in Chult essentially reports to him regarding their local activities, though they are a private organisation and are not commanded by him.
As well as private guards, groups of Zhentarim soldiers also patrol outside of the city, helping protect mining and lumbar operations. They have also been known to delve into the jungle proper for whatever aims they have outside of their employment in the city.