Christianity and Christian ethics have played a prominent role in the development of Western civilization, particularly around Europe during Late Antiquity and the Middle Ages. Following the Age of Discovery (15th–17th century), Christianity was spread into the Americas, Oceania, Sub-Saharan Africa and the rest of the world via missionary work and colonization.It is the world's most populous religious group, with over 2.4 billion followers, or 33% of the global population, comprising a majority of the population in about two-thirds of the countries in the world. Today, the four largest branches of Christianity are the Catholic Church (1.3 billion), Protestantism (920 million), the Eastern Orthodox Church (260 million) and Oriental Orthodoxy (86 million).