The Earth Was Created in 4004 BCE, Making It About 5,770 Years Old

Britannica's early editions incorporated the Ussher chronology, the most respected scholarly attempt to reconcile scripture with history, and its implication that Earth was merely thousands of years old. Ussher's work (1650) was methodical and academically rigorous for its time, and belief in a young Earth dominated Christian Europe well into the 1800s. However, geologists examining rock strata, fossil sequences, and the pace of erosion found mountains that couldn't have formed in thousands of years. Charles Lyell's *Principles of Geology* (1830) argued that existing processes, operating over vast timescales, could account for present landscapes. Darwin's *Origin of Species* (1859) required an Earth old enough for evolution by natural selection to occur. By the 1860s–1870s, geologists had amassed evidence suggesting the Earth was hundreds of millions of years old (modern estimates place it at 4.54 billion years). Britannica's later editions gradually shifted from Ussher's date to 'unknown antiquity' to eventually the modern geochronological consensus, representing one of the largest revisions in the encyclopedia's history.