Leonard Beadell OAM BEM FIEMS (21 April 1923 – 12 May 1995) was a surveyor, road builder, bushman, artist and author, responsible for constructing over 6,000 km (3,700 mi) of roads and opening up isolated desert areas – some 2.5 million square kilometres (970 thousand square miles) – of central Australia from 1947 to 1963. Born in West Pennant Hills, New South Wales, Beadell is sometimes called "the last true Australian explorer".

Beadell's paternal grandparents came from England in the mid-1870s. His father Fred Algernon Beadell was born in Sydney and mother Viola Pearl Mackay was from Townsville. They were married in Townsville on 19 December 1914, and soon moved to the Sydney area.

A daughter Phyllis was born in 1917, followed by Len in April 1923. Beadell's primary education began at Gladesville Public School, Ryde in 1928 and continued at Burwood Public School in 1930, both suburbs of Sydney.

At the suggestion of a school friend, Beadell joined the 1st Burwood Scout Troop where he met the scoutmaster John Richmond, who was to have a major influence on Beadell's life. Richmond had served in the army during World War I, and was employed as a draughtsman and surveyor for the Metropolitan Water, Sewerage and Drainage Board in Sydney.

Between 1931 and 1941, Beadell spent most weekends on bush survey trips with other scouts and Richmond, camping and searching for old survey marks. He learnt about the technical aspects of astronomical sightings and how to use a theodolite. In 1938 with a group of six scouts, Richmond took Beadell to Lord Howe Island where they took star sightings and determined that the mapped position of the island was out by about 10 kilometres (6.2 mi) in latitude.

Beadell finished his formal education at Sydney Grammar School in 1939. He went directly to a temporary surveying position with the water board in northern New South Wales, which had been arranged by Richmond.

At the age of 18 in 1941, Beadell received his call up notice for the army, and was keen to enlist. The service period was specified as the length of the war, plus twelve months. His initial service in the Citizen Military Force was in the Australian Army Service Corps at Bathurst, New South Wales, where he spent most of the time driving three ton trucks. In February 1942, he was transferred to the 2nd Australian Field Survey Company, and carried out contour surveys for army maps.

In September 1942, he transferred to the Australian Imperial Force and was transferred to the 2 Aust Field Survey Section, the topographical survey and mapping unit of the New Guinea Force. In October he sailed for New Guinea serving with the survey section, renamed the 8 Aust Field Survey Section AIF in January 1943, for thirteen months. Most of 1943 was spent in the Milne Bay locality. It was here that Beadell developed his artistic skills by watching army topographical draughtsmen, whose job it was to draw maps from information supplied by surveyors. He was transferred to the 2 Section 6 Aust Topographical Survey Company AIF in Australia, returning to Sydney in November 1943 for a period of leave and further survey work in Queensland.