George Everest in the context of "Fellow of the Royal Society"

Spherical Earth or Earth's curvature refers to the approximation of the figure of the Earth as a sphere. The earliest documented mention of the concept dates from around the 5th century BC, when it appears in the writings of Greek philosophers. In the 3rd century BC, Hellenistic astronomy established the roughly spherical shape of Earth as a physical fact and calculated the Earth's circumference. This knowledge was gradually adopted throughout the Old World during Late Antiquity and the Middle Ages, displacing earlier beliefs in a flat Earth. A practical demonstration of Earth's sphericity was achieved by Ferdinand Magellan and Juan Sebastián Elcano's circumnavigation (1519–1522).

The realization that the figure of the Earth is more accurately described as an ellipsoid dates to the 17th century, as described by Isaac Newton in Principia. In the early 19th century, the flattening of the earth ellipsoid was determined to be of the order of 1/300 (Delambre, Everest). The modern value as determined by the US DoD World Geodetic System since the 1960s is close to 1/298.25. The scientific study of the shape of the Earth is known as geodesy.

Lieutenant-Colonel William Lambton FRS (c. 1753 – 20 or 26 January 1823) was a British soldier, surveyor, and geographer who began a triangulation survey in 1800-1802 that was later called the Great Trigonometrical Survey of India. His initial survey was to measure the length of a degree of an arc of the meridian so as to establish the shape of the Earth and support a larger scale trigonometrical survey across the width of the peninsula of India between Madras and Mangalore. After triangulating across the peninsula, he continued surveys northwards for more than twenty years. He died during the course of the surveys in central India and is buried at Hinganghat in Wardha district of Maharashtra. He was succeeded by his assistant George Everest.

The Great Trigonometrical Survey of India was a project that aimed to carry out a survey across the Indian subcontinent with scientific precision. It was begun in 1802 by the British infantry officer William Lambton, under the auspices of the East India Company. Under the leadership of his successor, George Everest, the project was made the responsibility of the Survey of India. Everest was succeeded by Andrew Scott Waugh, and after 1861, the project was led by James Walker, who oversaw its completion in 1871.

Among the many accomplishments of the Survey were the demarcation of the British territories in the subcontinent and the measurement of the height of the Himalayan giants: Everest, K2, and Kangchenjunga. The Survey had an enormous scientific impact as well. It was responsible for one of the first accurate measurements of a section of an arc of longitude, and for measurements of the geodesic anomaly, which led to the development of the theories of isostasy.

The Survey of India is India's central engineering agency in charge of mapping and surveying. Set up in 1767 to help consolidate the territories of the British East India Company, it is one of the oldest Engineering Departments of the Government of India. Its members are from Survey of India Service cadre of Civil Services of India. It is headed by the Surveyor General of India. At present, the Surveyor General is Hitesh Kumar S. Makwana.

Major General Sir Andrew Scott Waugh (3 February 1810 – 21 February 1878) was a British army officer and Surveyor General of India who worked in the Great Trigonometrical Survey. He served under Sir George Everest and succeeded him in 1843. Waugh established a gridiron system of traverses for covering northern India. Waugh is credited with naming the peak of Mount Everest.