George and Elizabeth Kidman arrived in South Australia with their two sons in 1851. They had four more sons.
Sidney Kidman, born on 9 May 1857, was the last before his father died in June 1858. This left Elizabeth with five sons under the age of ten and expecting child number six, born in September 1858.
Elizabeth remarried, to Stephen Starr, a farmhand who apparently spent most of his time drinking and fighting. They had three more children, all girls, before Starr left her to settle in Melrose. Like his older brothers had done before him, Sidney left home as soon as he could. His mother Elizabeth died in 1873, leaving him a £1,000 inheritance, an exceptionally large amount for that time.
When Sidney Kidman left his Norwood home, he was thirteen years old and eventually would become 'a legend in his own lifetime'. Somehow it seemed to be a good way to become successful in life. Many other boys had done the same thing and done very well, including John Lewis.
Sidney Kidman found work at Kapunda and later Burra before moving to the Barrier Ranges where some of his older brothers worked. Eventually all except Tom Kidman worked on Mount Gipps Station. After being sacked on the spot for asking for more wages, Sidney Kidman set out on his own account in the transport, trade and butcher business.
During the 1880s Kidman made some very important decisions. He sold his share in the Broken Hill mine, which he came to regret for the rest of his life, went into partnership with his brother Sackville in 1884 and a year later married Bel Wright of Kapunda. These last two decisions were the best he ever made. In 1887 Kidman bought Thule Station, his first property, went into partnership with Jimmy Nicholas and established a coaching business which would break the Cobb & Co monopoly. Kidman & Nicholas coaches ran between Morgan and Cobar, Farina and Cordillo Downs, Marree and Birdsville and many other destinations in NSW and Queensland. When the Western Australian Goldfields opened up they bought out Cobb & Co there and employed Charlie Kidman to help them run it.
During the 1890s depression all, except the Western Australian, coaching businesses were sold and the Kidman partnership of Sackville and Sidney started to buy more cattle stations instead. It was also during this time that he shipped stock to the Western Australian goldfields through his agents Forrest and Emanuel. The first real big property bought by Kidman and his brother Sackville was Cowarie Station, pioneered by August Helling in 1875, which they acquired in 1895. A year later the Kidman brothers bought Owen Springs Station, south of Alice Springs. Within a few years they added Alton Downs, Annandale, Caryapundy, Clayton, Haddon Downs, Mount Nor'West, Pandi Pandi, Roseberth and Tickalara Stations.
Sackville Kidman died in March 1899 and from then on Sidney had to look after the running of everything, including the office and business in Broken Hill, which had always been managed by Sackville. Operating now on his own he established Eringa Station and later that same year bought Austral Downs and Carcoory. In 1900 Kidman, Alexander Forrest and Isadore Emanuel bought Victoria River Downs station in the Northern Territory and appointed Denis James Ronan as manager, but sold it again during the drought. On 23 May 1900 Kidman was also appointed a Justice of the Peace.
Although hurt badly during the severe drought of 1900-1903 when he lost more than 70,000 head of cattle and had to close several stations, he still managed to buy more stations and even a large house at Kapunda for his growing family. In 1903 he started on another buying spree and got hold of Carandotta and Lake Albert, which he sold within six months at a profit of $50,000. In 1904 he added Bullo Downs, Sandringham, Glengyle, Peake Downs and several others. Even while holidaying with his family in England he bought more properties, including Innamincka Station. When Mundowdna station, near Marree became available he snapped it up, acquiring a terminal at the end of the Birdsville Track where cattle could be fattened up before going on the train for the Adelaide market. Eventually he became the world's largest private landowner holding more land than the total area area of England, Ireland, Scotland and Wales.
Kidman paid his first visit to England at the age of 51 in 1908. He was then regarded as one of the most famous Australian of his day, and he caused a sensation when he decided to try and recruit new stockmen from the drivers of London's horse-drawn buses, which were being phased out in favour of petrol buses. Their drivers, who according to Kidman were excellent horsemen, would make good stockmen and hence were worthy of an attempt at poaching. About twenty of them accepted his invitation.
While in England Kidman ordered his first car, a 1909 Thornycroft four-seater, 18 HP, touring car, from John I. Thornycroft, whose wife was Kidman's second cousin. The car however took nearly a year to manufacture and ship to Adelaide, and wasn't registered to use until August 1910. Kidman found driving a car more tedious than he had expected. He now needed to concentrate to keep the car on the track unlike a horse-drawn vehicle which was kept on the track by the horse team. Soon the car had visible damage from making involuntary excursions off the road. In 1911, he gave it to his daughter Elma as a wedding present when she married Sid Reid.
In 1916 Kidman bought, with Edward Peter Tapp, Yancannia, Tindara and Lake Elder Stations.
During the First World War, Kidman gave more than generously for the war effort. His donations included wool, meat, horses, ambulances and planes. He promised his employees a job on their return and provided for the widows of those who did not. He also gave substantial donations to the Red Cross and the Salvation Army. In money terms it amounted to hundreds of thousands of dollars. By the end of the war Kidman was also diversifying his business. He became involved in ship and road building and railway and reservoir construction.
When Kidman moved his office and residence to Adelaide, he donated his Kapunda home in 1921 to the Education Department to be used as a High School. This building had been constructed for Alexander Greenshields in 1879. When Kidman bought it in 1901 he named it Eringa. He was knighted in 1921.
To celebrate Kidman's seventy-fifth birthday, his employees put on a rodeo in Adelaide on 3 September 1932, which was attended by nearly fifty thousand people. Even today it remains Australia's largest public birthday party ever for a private citizen. Les Daley wrote the poem Kidman's Boys for this special occasion.