Complex sentence: Although the majority of South Africans who emigrated went to Australia and New Zealand, countries with similar cultural and linguistic heritages (and similar climates), there was also a large number of South African immigrants that went to the United States.
Split into simpler sentences: Although the majority of South Africans who emigrated went to Australia and New Zealand, countries with similar cultural and linguistic heritages, as well as similar climates. There were also a large number of South African immigrants that went to the United States.