Charles William King (1818–1888) was a British scholar, writer, and collector, particularly renowned for his expertise in ancient gems and gemstones. Educated at Trinity College, Cambridge, he pursued academic interests without holding a formal parish position despite taking holy orders.

His significant contributions lie in his extensive research and collection of engraved gems, much of which was amassed in Italy. Due to declining eyesight, he sold his collection, which was ultimately presented to the Metropolitan Museum of Art in New York in 1881. King was widely acknowledged as a leading authority in his field, authoring several seminal works on antique gems, precious stones, and related numismatics. He also demonstrated a deep engagement with classical literature, translating significant works by Plutarch and Emperor Julian, and editing Horace.

Charles William King dedicated a significant portion of his life to the study and collection of engraved gems and precious stones. His formative experiences in Italy were crucial in building a substantial collection that later garnered widespread recognition. This collection, a testament to his deep knowledge and discerning eye, was eventually donated to the Metropolitan Museum of Art in New York. King's authority in this specialized field was universally acknowledged, leading him to produce several influential publications that remain important resources for understanding antique gems, their historical context, and their intrinsic value. His work extended beyond gemology to include early Christian numismatics, demonstrating a broad interest in ancient material culture.

Beyond his primary focus on gems, King possessed a profound familiarity with classical Greek and Latin literature, drawing heavily on authors like Pausanias and Pliny the Elder for insights relevant to his interests. While he appreciated the substance of these ancient texts, he was less concerned with minute textual analysis. His academic work also encompassed translations of important classical texts, including Plutarch's Moralia and the theosophical writings of Emperor Julian, making these accessible to a wider audience through Bohn's Classical Library. Notably, his work on "The Gnostics and their Remains" brought him into significant scholarly discourse, highlighting his engagement with early Christian and Gnostic thought.