Explique a seguinte expressão: "as primeiras cidades brasileiras nasceram no litoral."

Here's what I get  

Explanation:

In the mid-1600s, the Brazilians were in the middle of a long war with the Dutch, whom they eventually defeated.

Brazil's settlement and economic development was largely on its lengthy coastline. As a result of the Dutch war, the country built coastal forts to protect its local exports of sugar and tobacco.

Many of the cities of Brazil developed close to the protection of the forts. For example, Rio de Janeiro is surrounded by three historic forts.