The term "Sea Nomads" (or, somewhat more pejoratively, "Sea Gypsies") refers to a number of different ethnic groups mostly concentrated in Southeast Asia, though the Tanka people of southern China and the Jalia Kaibarta of eastern India have also been labeled as such. While these peoples are all different from one another, they have one fundamental thing in common: a maritime nomadic lifestyle.
As mentioned, these peoples are generally clustered around Southeast Asia. Your challenge is to have groups with similar lifestyles emerge elsewhere.
As mentioned, these peoples are generally clustered around Southeast Asia. Your challenge is to have groups with similar lifestyles emerge elsewhere.