Passage: In South Korea, a variety of different Asian people had migrated to the Korean Peninsula in past centuries, however few have remain permanent. South Korea and North Korea are among the world's most ethnically homogenous nations. Both North Korea and South Korea equate nationality or citizenship with membership in a single, homogenous ethnic group and politicized notion of "race."The common language and especially race are viewed as important elements by South Koreans in terms of identity, more than citizenship.

Question: What spoken thing is viewed as an important element?
common language