In 1920, David O. McKay embarked on a journey that forever changed the Church of Jesus Christ of Latter-day Saints. His visits to the Latter-day Saint missions, schools, and branches in the Pacific solidified the Church leadership’s commitment to global outreach. As importantly, the trip inspired McKay’s own initiatives when he later became Church president. McKay’s account of his odyssey brings to life the story of the Church of Jesus Christ’s transformation into a global faith. Throughout his diary, McKay expressed his humanity, curiosity, and fascination with cultures and places–the Maori hongi, East Asian customs, Australian wildlife, and more. At the same time, he and his travel companion, Hugh J. Cannon, detailed the Latter-day Saint missionary life of the era, closely observing logistical challenges and cultural differences, guiding various church efforts, and listening to followers’ impressions and concerns. Reid L. Neilson and Carson V. Teuscher’s meticulous notes provide historical, religious, and general context for the reader.Blending travelogue with history, Pacific Apostle illuminates the thought and work of an essential figure in the twentieth-century Church of Jesus Christ.