Clements R. Markham's Expeditions into the Valley of the Amazons, 1539, 1540, 1639 is a compelling historical account of three early European explorations into the heart of the Amazon Basin. Drawing from original documents and firsthand narratives, Markham reconstructs the journeys of the Spanish and Portuguese adventurers who ventured into the vast and mysterious rainforest, driven by ambition, conquest, and the search for legendary riches. The book details the 1539 and 1540 expeditions led by Gonzalo Pizarro and Francisco de Orellana, highlighting their perilous journey through dense jungles, encounters with Indigenous peoples, and Orellana's groundbreaking voyage down the Amazon River—the first European expedition to navigate its full length. Markham also examines the 1639 mission of Pedro Teixeira, the Portuguese explorer who ascended the river, further expanding European knowledge of the region. Through meticulous scholarship and engaging narrative, Markham brings these daring expeditions to life, offering insight into the explorers' struggles, the indigenous cultures they encountered, and the vast, untamed wilderness they sought to conquer. Expeditions into the Valley of the Amazons is an essential read for historians, explorers, and anyone fascinated by the Age of Discovery and the enduring mysteries of the Amazon.