Alec Kruger was born at Donkey Camp on the banks of the Katherine River on Christmas Day 1924. His mother, Yrambul Nungarai, or Polly, was a Mudpurra woman from Wave Hill. She married Frank Kruger, the son of German and Irish immigrants. As a child of mixed Aboriginal descent Alec was subject to the Aboriginal Ordinances of 1911. With his sister Gladys he was taken into institutional care at the age of three and a half.
At the age of ten, Kruger was sent to Loves Creek Station to work for the Bloomfield family. He was immediately put to work, helping with the droving and mustering of cattle and wild horses. In 1942, he discovered the Bloomfields were not placing his wages in a trust for him. Kruger was legally bound to the Bloomfields' employ and could not leave them without their permission. He planned his escape from the Bloomfields, waiting patiently for them to take him into Alice Springs to sell cattle from the 1942 muster. While Bloomfield was away from their camp in Alice Springs, he sneaked to the Army barracks and signed up, legally terminating his employment to the Bloomfields. By September 1945, he was discharged from the army.
After his discharge, he worked in various positions, such as a fettler (a railway worker checking the lines), road ganger (checking the surface of the highways), pearl diver and deckhand in Darwin, and as a drover. When he met and married Nita Palmer in 1955, Kruger chose employment which would not take him away from his family for long periods of time.
During the 1970s, Kruger became involved with politics. This in turn created problems in his marriage, and eventually he and his wife separated. Kruger took his son Larry to live with him in Katherine. However, after three years of separation he was reunited with his wife and they stayed together until her death in 1994.
Upon his return to his family and Alice Springs, Kruger worked for various Indigenous organisations, such as the Institute for Aboriginal Development (IAD), Congress (an Indigenous medical organisation that helps Indigenous Australians detox from alcohol) and the Centre for Appropriate Technology (CAT). When he retired he survived on his pension and money he earned from small jobs he did.
In the 1990s, Kruger became involved in various groups discussing the Stolen Generation. He was chosen to be a test case for the Stolen Generation. His court case Kruger vs The Commonwealth of Australia was dismissed.
In 2004, Kruger received a Northern Territory History grant to facilitate the research of his life for his biography, Alone on the Soaks. Later in 2006, Kruger participated in the Wordstorm Northern Territory Writers' Festival.
