What does this sentence mean? Brazil is also one of the countries with the largest number of Japanese overseas immigrants.

There are indeed many Japanese in Brazil. Japan immigrated to Brazil at the end of 19 and the beginning of the 20th century. At that time, Brazil lacked labor, slavery was abolished, and it was impossible to buy hard labor from Africa, so it wanted to introduce a group of immigrants from China. However, due to the conservative Qing government at that time, Japan's domestic population expanded, Japan cooperated with Brazil, and a large number of Japanese immigrated to Brazil. After the outbreak of the Pacific War, Japan originally intended to occupy Macao. Later, the Portuguese government asked Brazil to come forward (Brazilians are mainly Portuguese immigrants). Brazil warned Japan that if it declared war on Portugal and occupied Macao, it would expel the Japanese from China. During the whole war of aggression against China, Japan never dared to touch Macao.