Nat Buchanan was a great bushman and a good explorer. He knew the country from northern Queensland to Western Australia very well. He rarely made much money for himself though he was a pioneer on Bowen Downs, the Barkly Tableland, the Roper River, and the Victoria River. He pioneered the trail from the Kimberleys towards Perth. His brother William had also been a significant pastoralist pioneer. When he died, he owned almost no land but made possibilities for other men who often reaped where he had sown.
In 1859 Buchanan explored new country with William Landsborough, principally on the tributaries of the Fitzroy River, Queensland, when both suffered many privations and were found just in time by a rescue party. Buchanan then joined Landsborough and others as owners of Bowen Downs Station near Longreach, Queensland, which for a time, prospered. However, a time came when cattle were almost unsaleable, and the price of wool dropped so low that the station had to be given up, and Buchanan was practically penniless.
In October 1877, with a companion, Sam Croker, Buchanan began to investigate the country from the known regions around the Rankine to the overland telegraph line, around 800 kilometres away. Buchanan made several explorations inland from Bowen Downs, including securing land near Burketown, Queensland. They discovered much good new land, part of the Barkly Tableland, and have since carried some of the largest herds in Australia.
Throughout the 1870s and 1880s, Buchanan did much pioneering, working principally in northern Queensland and the Northern Territory. Buchanan was noted for his overlanding feats, including droving 20,000 head of cattle from Queensland to Glencoe Station.
He had another property, Wave Hill, for a period, but he lost this in 1894 because of a significant fall in cattle prices and difficulty getting markets. His son, Gordon Buchanan, had taken up land at Flora Valley in 1887, and Buchanan now established this as his headquarters. About two years later, with another man and an aboriginal boy, he started with camels and equipment the South Australian government provided to find a stock route from northern Queensland.
He went from Oodnadatta up the line to Tennant Creek and then westward to Sturt’s Creek. About 64 kilometres from Hooker’s Creek, he sighted the hills now named Buchanan Hills and came to a branch of Hooker’s Creek the next day.
Then he went to Hale’s Creek, the Sturt, and Flora Valley. Attempts were made to find a practicable stock route to the west but failed. Returning to Flora Creek, he prepared a report for the South Australian government, which added much to the knowledge of the country, though Buchanan had failed in his main object.
In 1899 Buchanan, now 73 years of age, bought a farm on Dungowan Creek, 35 kilometres (22 mi) from Tamworth, and he died there in 1901, still working. He married Catherine Gordon in 1863, who survived him, along with a son. Nat was buried in the general cemetery at Walcha, New South Wales.