Final answer:
The city with the largest Portuguese population outside of Lisbon is São Paulo, Brazil, due to its cultural ties as a former Portuguese colony and its rich immigration history.
Step-by-step explanation:
The city with the largest Portuguese population outside of Lisbon is São Paulo, Brazil. Given the historical context that Brazil was once a Portuguese colony, its culture is profoundly influenced by European immigration. Over time, the descendants of Portuguese settlers, alongside those of many other cultural groups, have established a significant Portuguese community within São Paulo. Furthermore, the history of Portuguese exploration and colonization, which extended beyond Europe to Africa and eventually the new Brazilian territory, has fostered a diverse cultural heritage in South America, especially in Brazil's populous cities.